Use of corrosion inhibitors for fuels and lubricants

ABSTRACT

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

The present invention relates to novel uses of corrosion inhibitors infuels and lubricants.

Corrosion inhibitors are standard additives in fuels and lubricants,which are often based on structures containing acid groups, for exampledimer fatty acids.

A disadvantage of these corrosion inhibitors is that they have atendency to precipitate, especially in the presence of calcium ions, asa result of which their corrosion-inhibiting action is reduced. Thedeposits formed as a result of this precipitation can additionallyimpair the working of engines, engine constituents or parts of the fuelsystem, especially the injection system, specifically the injectionpumps or nozzles.

The “injection system” is understood to mean the part of the fuel systemin motor vehicles from the fuel pump up to and including the injectoroutlet. The “fuel system” is understood to mean the components of motorvehicles that are in contact with the particular fuel, preferably theregion from the tank up to and including the injector outlet.

In one embodiment of the present invention, the compounds of theinvention are to act against deposits not just in the injection systembut also in the rest of the fuel system, and here especially againstdeposits in fuel filters and pumps.

The problem addressed is that of providing corrosion inhibitors whichexhibit increased compatibility with calcium ions and at the same timeretain their action as a corrosion inhibitor.

The problem is solved by the use according to the claims.

WO 2006/135881 describes quaternized ammonium salts prepared bycondensation of a hydrocarbyl-substituted acylating agent and of anoxygen or nitrogen atom-containing compound with a tertiary amino group,and subsequent quaternization by means of hydrocarbyl epoxide in thepresence of stoichiometric amounts of an acid such as, moreparticularly, acetic acid. Further quaternizing agents claimed in WO2006/135881 are dialkyl sulfates, benzyl halides andhydrocarbyl-substituted carbonates, and dimethyl sulfate, benzylchloride and dimethyl carbonate have been studied experimentally.

In none of these documents is the anticorrosive action of thesecompounds recognized.

WO 2014/195464 discloses the use of quaternized ammonium salts forprevention and elimination of deposits in the operation of dieselengines. Also disclosed are examples which show an anticorrosive effectof ammonium salts in metal-free diesel fuels on steel samples. Inaddition, WO 2014/195464 discloses the use of quaternized ammonium saltsfor reducing the level of deposits in the intake system of a gasolineengine, such as, more particularly, DISI and PFI (port fuel injector)engines. According to the examples, deposits in injectors of directinjection gasoline engines are prevented and deposits formed beforehandare removed. However, WO 2014/195464 does not comprise any disclosurerelating to the cleanliness of valves in intake manifold gasolineengines.

Accordingly, the invention provides for the use of a reaction productcomprising a quaternized nitrogen compound or of a component fractionthereof which comprises a quaternized nitrogen compound and has beenobtained from the reaction product by purification, wherein the reactionproduct is obtainable by

-   -   reacting a quaternizable nitrogen compound comprising at least        one quaternizable, especially tertiary, amino group with a        quaternizing agent which converts the at least one        quaternizable, especially tertiary, amino group to a quaternary        ammonium group,    -   wherein the quaternizing agent is a hydrocarbyl epoxide in        combination with a free hydrocarbyl-substituted polycarboxylic        acid,        as corrosion inhibitors in fuels having a content of alkali        metals and/or alkaline earth metals and/or zinc of at least 0.1        ppm by weight.

The reaction products described show a particular advantage in fuelshaving a content of alkali metals and/or alkaline earth metals and/orzinc of at least 0.1 ppm by weight, more preferably at least 0.2 ppm byweight and even more preferably at least 0.3 ppm by weight andespecially at least 0.5 ppm by weight. Also conceivable is a content ofalkali metals and/or alkaline earth metals and/or zinc of at least 1 ppmby weight, preferably at least 2 and more preferably at least 3 ppm byweight.

The present invention further provides for the use of a reaction productcomprising a quaternized nitrogen compound or of a component fractionthereof which comprises a quaternized nitrogen compound and has beenobtained from the reaction product by purification, wherein the reactionproduct is obtainable by

-   -   reacting a quaternizable nitrogen compound comprising at least        one quaternizable, especially tertiary, amino group with a        quaternizing agent which converts the at least one        quaternizable, especially tertiary, amino group to a quaternary        ammonium group,    -   wherein the quaternizing agent is a hydrocarbyl epoxide in        combination with a free hydrocarbyl-substituted polycarboxylic        acid,        as corrosion inhibitors in gasoline fuels, preferably in        gasoline fuels having a content of alkali metals and/or alkaline        earth metals and/or zinc of at least 0.1 ppm by weight, more        preferably at least 0.2 ppm by weight and even more preferably        at least 0.3 ppm by weight and especially at least 0.5 ppm by        weight. Also conceivable is a content of alkali metals and/or        alkaline earth metals and/or zinc of at least 1 ppm by weight,        preferably at least 2 and more preferably at least 3 ppm by        weight.

The present invention further provides for the use of a reaction productcomprising a quaternized nitrogen compound or of a component fractionthereof which comprises a quaternized nitrogen compound and has beenobtained from the reaction product by purification, wherein the reactionproduct is obtainable by

-   -   reacting a quaternizable nitrogen compound comprising at least        one quaternizable, especially tertiary, amino group with a        quaternizing agent which converts the at least one        quaternizable, especially tertiary, amino group to a quaternary        ammonium group,    -   wherein the quaternizing agent is a hydrocarbyl epoxide in        combination with a free hydrocarbyl-substituted polycarboxylic        acid,        in fuels, preferably in fuels having a content of alkali metals        and/or alkaline earth metals and/or zinc of at least 0.1 ppm by        weight, more preferably at least 0.2 ppm by weight and even more        preferably at least 0.3 ppm by weight and especially at least        0.5 ppm by weight, for reducing the corrosion of nonferrous        metals, particularly copper and copper-containing alloys. Also        conceivable is a content of alkali metals and/or alkaline earth        metals and/or zinc of at least 1 ppm by weight, preferably at        least 2 and more preferably at least 3 ppm by weight.

It is an advantage of the reaction products described that they alsoexhibit their corrosion-inhibiting action in the presence of alkalimetals and/or alkaline earth metals and/or zinc, preferably also in thepresence of alkaline earth metals. The content of alkali metals and/oralkaline earth metals in fuels results, for example, from mixing withlubricants containing alkali metals and/or alkaline earth metals, forexample in the fuel pump. In addition, alkali metals and/or alkalineearth metals may originate from non-desalinated or inadequatelydesalinated fuel additives, for example carrier oils. The entrainment ofalkali metals and/or alkaline earth metals into the fuels can cause theabovementioned disadvantages. One example of a zinc source is antiwearadditives.

Alkali metals include particularly sodium and potassium, especiallysodium.

Alkaline earth metals include particularly magnesium and calcium,especially calcium.

Zinc should also be emphasized.

Particularly advantageously, the reaction products described are stillactive even in the presence of calcium and do not exhibit anyprecipitation.

The stated amounts of alkali metals and/or alkaline earth metals and/orzinc each relate to individual metal species.

It is a further advantage of the compounds of the invention that theyincrease the conductivity of fuels.

A fuel is generally a very poor electrical conductor. Therefore,electrical charges have a tendency to accumulate locally in such anorganic material and to discharge as sparks in an uncontrolled manner,which can lead to explosion or fire on contact of this fuel, which iscombustible and highly flammable by nature, with air or oxygen. By meansof suitable antistatic additives, it is possible to increase theelectrical conductivity of fuels, such that it is no longer possible forstatic charges to form and the risk of explosion and fire is reduced.

Therefore, it is a further object of the present invention to use thequaternary compounds described as a novel and improved additiveformulation suitable for antistatic modification and improvement of theelectrical conductivity of fuels and for prevention of electrostaticcharging in chemical and physical processes, as is the use of thequaternary compounds described for improving the electrical conductivityand for reducing electrostatic charging of fuels.

The present invention further provides for the use of a reaction productcomprising a quaternized nitrogen compound or of a component fractionthereof which comprises a quaternized nitrogen compound and has beenobtained from the reaction product by purification, wherein the reactionproduct is obtainable by

-   -   reacting a quaternizable nitrogen compound comprising at least        one quaternizable, especially tertiary, amino group with a        quaternizing agent which converts the at least one        quaternizable, especially tertiary, amino group to a quaternary        ammonium group,    -   wherein the quaternizing agent is a hydrocarbyl epoxide in        combination with a free hydrocarbyl-substituted polycarboxylic        acid,        for complete or partial prevention of the new formation of        deposits and/or complete or partial removal of existing deposits        in fuel inlet and/or outlet valves of gasoline engines having        port fuel injectors (PFI).

Preference is given to eliminating deposits in the intake valves of portfuel injector engines, called IVD (intake valve deposits).

BRIEF DESCRIPTION OF THE INVENTION

It has now been found that, surprisingly, the above problem is solved byproviding quaternized nitrogen compounds, for example hydrocarbylaminecompounds, and fuel and lubricant compositions additized therewith.

Surprisingly, the additives of the invention as illustrated moreparticularly by the use examples appended are surprisingly effective ascorrosion inhibitors in fuels, preferably in gasoline or diesel fuels,more preferably in gasoline fuels.

DETAILED DESCRIPTION OF THE INVENTION A1) Specific Embodiments

The present invention relates especially to the following specificembodiments:

-   1. The use of an effective amount of at least one reaction product    comprising a quaternized nitrogen compound or a component fraction    thereof which comprises a quaternized nitrogen compound and has been    obtained from the reaction product by purification, wherein the    reaction product is obtainable by    -   reacting a quaternizable nitrogen compound, for example a        quaternizable alkylamine, comprising at least one quaternizable,        especially tertiary, amino group with a quaternizing agent which        converts the at least one quaternizable, especially tertiary,        amino group to a quaternary ammonium group, wherein the        quaternizing agent is a hydrocarbyl epoxide in combination with        a free hydrocarbyl-substituted polycarboxylic acid, as corrosion        inhibitor in fuels or lubricants, preferably in fuels,        particularly preferably in fuels having a content of alkali        metals and/or alkaline earth metals and/or zinc of at least 0.1        ppm by weight.-   2. The use according to embodiment 1, wherein the quaternizable    nitrogen compound is selected from a) at least one alkylamine    comprising at least one compound of the following general formula 3

R_(a)R_(b)R_(c)N  (3)

-   -   in which    -   at least one of the R_(a), R_(b) and R_(c) radicals, for example        one or two, is a straight-chain or branched, saturated or        unsaturated C₈-C₄₀-hydrocarbyl radical (especially        straight-chain or branched C₈-C₄₀-alkyl), and the other radicals        are identical or different, straight-chain or branched,        saturated or unsaturated C₁-C₆-hydrocarbyl radicals (especially        C₁-C₆-alkyl);    -   b) at least one polyalkene-substituted amine comprising at least        one quaternizable, especially tertiary, amino group;    -   c) at least one polyether-substituted amine comprising at least        one quaternizable, especially tertiary, amino group; and    -   d) at least one reaction product of a hydrocarbyl-substituted        acylating agent and a compound comprising a nitrogen or oxygen        atom and additionally comprising at least one quaternizable,        especially tertiary, amino group; and    -   e) mixtures thereof.    -   or

-   2a. The use according to embodiment 1, wherein the quaternizable    nitrogen compound is, for example, an alkylamine comprising at least    one compound of the following general formula 3:

R_(a)R_(b)R_(c)N  (3)

-   -   in which all the R_(a), R_(b) and R_(c) radicals are identical        or different, straight-chain or branched, saturated or        unsaturated C₈-C₄₀-hydrocarbyl radicals, especially        straight-chain or branched C₈-C₄₀-alkyl radicals.

-   3. The use according to either of embodiments 1 and 2, wherein the    quaterizing agent comprises an epoxide of the general formula 4

-   -   where    -   the R_(d) radicals present therein are the same or different and        are each H or a hydrocarbyl radical, the hydrocarbyl radical        being an aliphatic or aromatic radical having at least 1 to 10        carbon atoms.

-   4. The use according to any of embodiments 1 to 3, wherein the free    acid of the quaternizing agent is a hydrocarbyl-substituted C₃-C₂a    dicarboxylic acid.

-   5. The use according to any of the embodiments 1 to 4, wherein the    hydrocarbyl substituent of the carboxylic acid is a polyalkylene    radical having a polymerization level of 2 to 100, or 3 to 50 or 4    to 25.

-   6. The use according to any of the preceding embodiments, wherein    the quaternizable tertiary amine is a compound of the formula 3 in    which at least two of the R_(a), R_(b) and R_(c) radicals are the    same or different and are each a straight-chain or branched    C₁₀-C₂₀-alkyl radical and the other radical is C₁-C₄-alkyl.

-   7. The use according to any of the preceding embodiments, wherein    the quaternizing agent is selected from lower alkylene oxides in    combination with a hydrocarbyl-substituted polycarboxylic acid

-   8. The use according to any of the preceding embodiments, selected    from diesel fuels, biodiesel fuels, gasoline fuels, and    alkanol-containing gasoline fuels, such as bioethanol-containing    fuels, especially gasoline fuels.

“Component fraction” is preferably understood to mean that the reactionproduct is freed or depleted of unconverted reactants, particularlyhydrocarbyl epoxide, and any by-products, leaving the quaternizednitrogen compound and hydrocarbyl-substituted polycarboxylic acid atleast partly together in the component fraction.

In one embodiment of the present invention, preference is given to theuse of the reaction product comprising a quaternized nitrogen compoundover the use of the component fraction thereof obtained by purification.

Test methods suitable in each case for verification of theabove-designated applications are known to those skilled in the art, orare described in the experimental section which follows, to whichgeneral reference is hereby made explicitly.

A2) General Definitions

In the absence of statements to the contrary, the following generaldefinitions apply:

“Quaternizable” nitrogen groups or amino groups comprise especiallyprimary, secondary and, in particular, tertiary amino groups.

“Hydrocarbyl” should be interpreted broadly and comprises bothlong-chain and short-chain, straight-chain and branched hydrocarbylradicals having 1 to 50 carbon atoms, which may optionally additionallycomprise heteroatoms, for example O, N, NH, S, in the chain thereof. Aspecific group of hydrocarbyl radicals comprises both long-chain andshort-chain, straight-chain or branched alkyl radicals having 1 to 1000,3 to 500 4 to 400 carbon atoms.

“Long-chain” or “high molecular weight” hydrocarbyl radicals arestraight-chain or branched hydrocarbyl radicals and have 7 to 50 or 8 to50 or 8 to 40 or 10 to 20 carbon atoms, which may optionallyadditionally comprise heteroatoms, for example O, N, NH, S, in the chainthereof. In addition, the radicals may be mono- or polyunsaturated andhave one or more noncumulated, for example 1 to 5, such as 1, 2 or 3,C═C double bonds or C—C triple bonds, especially 1, 2 or 3 double bonds.They may be of natural or synthetic origin.

They may also have a number-average molecular weight (M_(n)) of 85 to 20000, for example 113 to 10 000, or 200 to 10 000 or 350 to 5000, forexample 350 to 3000, 500 to 2500, 700 to 2500, or 800 to 1500. In thatcase, they are more particularly formed essentially from C₂₋₆,especially C₂₋₄, monomer units such as ethylene, propylene, n- orisobutylene or mixtures thereof, where the different monomers may becopolymerized in random distribution or as blocks. Such long-chainhydrocarbyl radicals are also referred to as polyalkylene radicals orpoly-C₂₋₆- or poly-C₂₋₄-alkylene radicals. Suitable long-chainhydrocarbyl radicals and the preparation thereof are also described, forexample, in WO 2006/135881 and the literature cited therein.

Examples of particularly useful polyalkylene radicals are polyisobutenylradicals derived from what are called “high-reactivity” polyisobuteneswhich feature a high content of terminal double bonds. Terminal doublebonds are alpha-olefinic double bonds of the type

which are also referred to collectively as vinylidene double bonds.Suitable high-reactivity polyisobutenes are, for example, polyisobuteneswhich have a proportion of vinylidene double bonds of greater than 70mol %, especially greater than 80 mol % or greater than 85 mol %.Preference is given especially to polyisobutenes which have homogeneouspolymer skeletons. Homogeneous polymer skeletons are possessedespecially by those polyisobutenes formed from isobutene units to anextent of at least 85% by weight, preferably to an extent of at least90% by weight and more preferably to an extent of at least 95% byweight. Such high-reactivity polyisobutenes preferably have anumber-average molecular weight within the abovementioned range. Inaddition, the high-reactivity polyisobutenes may have a polydispersityin the range from 1.05 to 7, especially of about 1.1 to 2.5, for exampleof less than 1.9 or less than 1.5. Polydispersity is understood to meanthe quotient of weight-average molecular weight Mw divided by thenumber-average molecular weight Mn.

Particularly suitable high-reactivity polyisobutenes are, for example,the Glissopal brands from BASF SE, especially Glissopal) 1000 (Mn=1000),Glissopal® V 33 (Mn=550), and Glissopal® 2300 (Mn=2300), and mixturesthereof. Other number-average molecular weights can be established in amanner known in principle by mixing polyisobutenes of differentnumber-average molecular weights or by extractive enrichment ofpolyisobutenes of particular molecular weight ranges.

A specific group of long-chain hydrocarbyl radicals comprisesstraight-chain or branched alkyl radicals (“long-chain alkyl radicals”)having 8 to 50, for example 8 to 40 or 8 to 30 or 10 to 20, carbonatoms.

A further group of specific long-chain hydrocarbyl radicals comprisespolyalkylene radicals which are especially formed essentially from C₂₋₆,especially C₂₋₄, monomer units, such as ethylene, propylene, n- orisobutylene or mixtures thereof and have a degree of polymerization of 2to 100, or 3 to 50 or 4 to 25.

“Short-chain hydrocarbyl” or “low molecular weight hydrocarbyl” isespecially straight-chain or branched alkyl or alkenyl, optionallyinterrupted by one or more, for example 2, 3 or 4, heteroatom groupssuch as —O— or —NH—, or optionally mono- or polysubstituted, for exampledi-, tri- or tetrasubstituted.

“Hydrocarbylene” represents straight-chain or singly or multiplybranched bridge groups having 1 to 10 carbon atoms, optionallyinterrupted by one or more, for example 2, 3 or 4, heteroatom groupssuch as —O— or —NH—, or optionally mono- or polysubstituted, for exampledi-, tri- or tetrasubstituted.

“Alkyl” or “lower alkyl” represents especially saturated, straight-chainor branched hydrocarbon radicals having 1 to 4, 1 to 5, 1 to 6, or 1 to7, carbon atoms, for example methyl, ethyl, n-propyl, 1-methylethyl,n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, n-pentyl,1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl,1-ethylpropyl, n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl,2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl,1-ethyl-1-methylpropyl and 1-ethyl-2-methylpropyl; and also n-heptyl,and the singly or multiply branched analogs thereof.

“Long-chain alkyl” represents, for example, saturated straight-chain orbranched hydrocarbyl radicals having 8 to 50, for example 8 to 40 or 8to 30 or 10 to 20, carbon atoms, such as octyl, nonyl, decyl, undecyl,dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl,octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl,tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl,squalyl, constitutional isomers, especially singly or multiply branchedisomers and higher homologs thereof.

“Hydroxyalkyl” represents especially the mono- or polyhydroxylated,especially monohydroxylated, analogs of the above alkyl radicals, forexample the monohydroxylated analogs of the above straight-chain orbranched alkyl radicals, for example the linear hydroxyalkyl groups, forexample those having a primary (terminal) hydroxyl group, such ashydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl, or thosehaving nonterminal hydroxyl groups, such as 1-hydroxyethyl, 1- or2-hydroxypropyl, 1- or 2-hydroxybutyl or 1-, 2- or 3-hydroxybutyl.

“Alkenyl” represents mono- or polyunsaturated, especiallymonounsaturated, straight-chain or branched hydrocarbyl radicals having2 to 4, 2 to 6, or 2 to 7 carbon atoms and one double bond in anyposition, e.g. C₂-C₆-alkenyl such as ethenyl, 1-propenyl, 2-propenyl,1-methylethenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl,2-methyl-1-propenyl, I-methyl-2-propenyl, 2-methyl-2-propenyl,1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-methyl-1-butenyl,2-methyl-1-butenyl, 3-methyl-1-butenyl, 1-methyl-2-butenyl,2-methyl-2-butenyl, 3-methyl-2-butenyl, 1-methyl-3-butenyl,2-methyl-3-butenyl, 3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl,1,2-dimethyl-1-propenyl, 1,2-dimethyl-2-propenyl, 1-ethyl-1-propenyl,1-ethyl-2-propenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl,5-hexenyl, 1-methyl-1-pentenyl, 2-methyl-1-pentenyl,3-methyl-1-pentenyl, 4-methyl-1-pentenyl, 1-methyl-2-pentenyl,2-methyl-2-pentenyl, 3-methyl-2-pentenyl, 4-methyl-2-pentenyl,1-methyl-3-pentenyl, 2-methyl-3-pentenyl, 3-methyl-3-pentenyl,4-methyl-3-pentenyl, 1-methyl-4-pentenyl, 2-methyl-4-pentenyl,3-methyl-4-pentenyl, 4-methyl-4-pentenyl, 1-dimethyl-2-butenyl,1,1-dimethyl-3-butenyl, 1,2-dimethyl-1-butenyl, 1,2-dimethyl-2-butenyl,1,2-dimethyl-3-butenyl, 1,3-dimethyl-1-butenyl, 1,3-dimethyl-2-butenyl,1,3-dimethyl-3-butenyl, 2,2-dimethyl-3-butenyl, 2,3-dimethyl-1-butenyl,2,3-dimethyl-2-butenyl, 2,3-dimethyl-3-butenyl, 3,3-dimethyl-1-butenyl,3,3-dimethyl-2-butenyl, 1-ethyl-1-butenyl, 1-ethyl-2-butenyl,1-ethyl-3-butenyl, 2-ethyl-1-butenyl, 2-ethyl-2-butenyl,2-ethyl-3-butenyl, 1,1,2-trimethyl-2-propenyl,1-ethyl-1-methyl-2-propenyl, 1-ethyl-2-methyl-1-propenyl and1-ethyl-2-methyl-2-propenyl.

“Hydroxyalkenyl” represents especially the mono- or polyhydroxylated,especially monohydroxylated, analogs of the above alkenyl radicals.

“Aminoalkyl” and “aminoalkenyl” represent especially the mono- orpolyaminated, especially monoaminated, analogs of the above alkyl andalkenyl radicals respectively, or analogs of the above hydroxyalkylwhere the OH group has been replaced by an amino group.

“Alkylene” represents straight-chain or singly or multiply branchedhydrocarbyl bridging groups having 1 to 10 carbon atoms, for exampleC₁-C₇-alkylene groups selected from —CH—, —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄—,—(CH₂)₂—CH(CH₃)—, —CH₂—CH(CH₃)—CH₂, (CH₂)₄—, —(CH₂)₅—, —(CH₂)₆,—(CH₂)₇—, —CH(CH₃)—CH₂—CH₂—CH(CH₃)— or —CH(CH₃)—CH₂—CH₂—CH₂—CH(CH₃)— orC₁-C₄-alkylene groups selected from —CH₂—, —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄—,—(CH₂)₂—CH(CH₃)—, —CH₂—CH(CH₃)—CH₂—or C₂-C₆-alkylene groups, for example

—CH₂—CH(CH₃)—, —CH(CH₃)—CH₂, —CH(CH₃)—CH(CH₃)—, —C(CH₃)₂—CH₂—,—CH₂—C(CH₃)₂—, —C(CH₃)₂—CH(CH₃)—, —CH(CH₃)—C(CH₃)₂—, —CH₂—CH(Et)-,—CH(CH₂CH₃)—CH₂—, —CH(CH₂CH₃)—CH(CH₂CH₃)—, —C(CH₂CH₃)₂CH₂—,—CH₂—C(CH₂CH₃)₂—, —CH₂—CH(n-propyl)-, —CH(n-propyl)-CH₂—,—CH(n-propyl)—CH(CH₃)—, —CH₂—CH(n-butyl)-, —CH(n-butyl)-CH₂—,—CH(CH₃)—CH(CH₂CH₃)—, —CH(CH₃)—CH(n-propyl)-, —CH(CH₂CH₃)—CH(CH₃)—,—CH(CH₃)—CH(CH₂CH₃)—, or C₂-C₄-alkylene groups, for example selectedfrom —(CH₂)₂—, —CH₂—CH(CH₃)—, —CH(CH₃)—CH₂—, —CH(CH₃)—CH(CH₃)—,—C(CH₃)₂—CH₂—, —CH₂—C(CH₃)₂—, —CH₂—CH(CH₂CH₃)—, —CH(CH₂CH₃)—CH₂—.

Oxyalkylene radicals correspond to the definition of the abovestraight-chain or singly or multiply branched alkylene radicals having 2to 10 carbon atoms, where the carbon chain may be interrupted once ormore than once, especially once, by an oxygen heteroatom. Nonlimitingexamples include: —CH₂—O—CH₂—, —(CH₂)₂—O—(CH₂)₂—, —(CH₂)₃—O—(CH₂)₃—, or—CH₂—O—(CH₂)₂—, —(CH₂)₂—O—(CH₂)₃—, —CH₂—O—(CH₂)₃.

Aminoalkylene corresponds to the definition of the above straight-chainor singly or multiply branched alkylene radicals having 2 to 10 carbonatoms, where the carbon chain may be interrupted once or more than once,especially once, by a nitrogen group (especially —NH-group). Nonlimitingexamples include: —CH₂NH—CH₂—, —(CH₂)₂—NH—(CH₂)₂—, —(CH₂)₃—NH—(CH₂)₃—,or —CH₂—NH—(CH₂)₂—, —(CH₂)₂—NH—(CH₂)₃—, —CH₂—NH—(CH₂)₃.

“Alkenylene” represents the mono- or polyunsaturated, especiallymonounsaturated, analogs of the above alkylene groups having 2 to 10carbon atoms, especially C₂-C₇-alkenylenes or C₂-C₄-alkenylene, such as—CH═CH—, —CH═CH—CH₂—, —CH₂—CH═CH—, —CH═CH—CH₂—CH₂—, —CH₂—CH═CH—CH₂—,—CH₂—CH₂—CH═CH—, —CH(CH₃)—CH═CH—, —CH₂—C(CH₃)═CH—.

“Cycloalkyl” represents carbocyclic radicals having 3 to 20 carbonatoms, for example C₃-C₁₂-cycloalkyl such as cyclopropyl, cydobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl,cyclodecyl, cycloundecyl and cyclododecyl; preference is given tocyclopentyl, cyclohexyl, cycloheptyl, and also to cyclopropylmethyl,cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl,cyclopentylethyl, cyclohexylmethyl, or C₃-C₇-cycloalkyl such ascyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl,cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclopentylethyl,cyclohexylmethyl, where the bond to the rest of the molecule may be viaany suitable carbon atom.

“Cydoalkenyl” or mono- or polyunsaturated cycloalkyl representsespecially monocyclic, mono- or polyunsaturated hydrocarbyl groupshaving 5 to 8, preferably to 6, carbon ring members, for example themonounsaturated radicals cyclopenten-1-yl, cyclopenten-3-yl,cyclohexen-1-yl, cyclohexen-3-yl and cyclohexen-4-yl.

“Aryl” represents mono- or polycyclic, preferably mono- or bicyclic,optionally substituted aromatic radicals having 6 to 20, for example 6to 10, ring carbon atoms, for example phenyl, biphenyl, naphthyl such as1- or 2-naphthyl, tetrahydronaphthyl, fluorenyl, indenyl andphenanthrenyl. These aryl radicals may optionally bear 1, 2, 3, 4, 5 or6 identical or different substituents.

“Alkylaryl” represents analogs of the above aryl radicals mono- orpolyalkyl-substituted, especially mono- or dialkyl-substituted, in anyring position, where aryl is likewise as defined above, for exampleC₁-C₄-alkylphenyl, where the C₁-C₄-alkyl radicals may be in any ringposition.

“Substituents” for radicals specified herein are especially, unlessstated otherwise, selected from keto groups, —COOH, —COO-alkyl, —OH,—SH, —CN, amino, —NO₂, alkyl, or alkenyl groups.

“Mn” represents the number-average molecular weight and is determined ina conventional manner; more particularly, such figures relate to Mnvalues determined by relative methods, such as gel permeationchromatography with THF as the eluent and polystyrene standards, orabsolute methods, such as vapor phase osmometry using toluene as thesolvent.

“Mw” represents the weight-average molecular weight and is determined ina conventional manner; more particularly, such figures relate to Mwvalues determined by relative methods, such as gel permeationchromatography with THF as the eluent and polystyrene standards, orabsolute methods, such as light scattering.

The “degree of polymerization” usually refers to the numerical meandegree of polymerization (determination method: gel permeationchromatography with THF as the eluent and polystyrene standards; orGC-MS coupling).

A3) Quaternizable Nitrogen Compounds

Quaternizable nitrogen compounds are especially:

A3.1) Tertiary Amines

Tertiary amines are especially compounds of the above formula (3) andare compounds known per se, as described, for example, in EP-A-2 033945.

The tertiary amine reactant (3) preferably bears a segment of theformula NR_(a)R_(b) where one of the radicals has an alkyl group having8 to 40 carbon atoms and the other an alkyl group having up to 40 andmore preferably 8 to 40 carbon atoms. The R_(c) radical is especially ashort-chain C₁-C₆-alkyl radical, such as a methyl, ethyl or propylgroup. R_(a) and R_(b) may be straight-chain or branched, and/or may bethe same or different. For example, R_(a) and R_(b) may be astraight-chain C₁₂-C₂₄-alkyl group. Alternatively, only one of the tworadicals may be long-chain (for example having 8 to 40 carbon atoms),and the other may be a methyl, ethyl or propyl group.

Appropriately, the NR_(a)R_(b) segment is derived from a secondaryamine, such as dioctadecylamine, dicocoamine, hydrogenated ditallowamineand methylbehenylamine. Amine mixtures as obtainable from naturalmaterials are likewise suitable. One example is a secondary hydrogenatedtallowamine where the alkyl groups are derived from hydrogenated tallowfat, and contain about 4% by weight of C₁₄, 31% by weight of C₁₆ and 59%by weight of C₁₈-alkyl groups. Corresponding tertiary amines of theformula (3) are sold, for example, by Akzo Nobel under the Armeen® M2HTor Armeen® M2C name.

However, the tertiary amine reactant (3) may also be one where theR_(a), R_(b) and R_(c) radicals have identical or different long-chainalkyl radicals, especially straight-chain or branched alkyl groupshaving 8 to 40 carbon atoms.

However, the tertiary amine reactant (3) may also be one where theR_(a), R_(b) and R_(c) radicals have identical or different short-chainalkyl radicals, especially straight-chain or branched alkyl groupshaving 1 to 7 or especially 1 to 4 carbon atoms.

Further nonlimiting examples of suitable amines are:

N,N-dimethyl-N-(2-ethylhexyl)amine,N,N-dimethyl-N-(2-propylheptyl)amine, dodecyl-dimethylamine,hexadecyldimethylamine, oleyldimethylamine, stearyldimethylamine,heptadecyldimethylamine, cocoyldimethylamine, dicocoylmethylamine,tallowdimethylamine, ditallowmethylamine, tridodecylamine,trihexadecylamine, trioctadecylamine, soyadimethylamine,tris(2-ethylhexyl)amine, and Alamine 336 (tri-n-octylamine).

Nonlimiting examples of short-chain tertiary amines are: trimethylamine,triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine,tri-n-hexylamine, tri-n-heptylamine, ethyldimethylamine,dimethylethylamine, n-propyldimethylamine, isopropyldimethylamine,n-propyldiethylamine, isopropyldiethylamine, n-butyldimethylamine,n-butyldiethylamine. n-butyldipropylamine.

Short-chain triamines are also appropriate especially when thequaternizing agent (see below) bears one or more alkyl radicals R_(d)having more than one carbon atom or one or more aromatic radicals R_(d).

A3.2) Quaternizable, Polyether-Substituted Amine Comprising at Least OneQuaternizable, Especially Tertiary, Amino Group:

Compounds of this kind are described, for example, in the applicant'sWO2013/064689, which is hereby explicitly incorporated by reference.

Substituted amines of this kind especially have at least one, especiallyone, polyether substituent having monomer units of the general formulaIc

—[(—CH(R₃)—CH(R₄)—O—]-  (Ic)

in whichR₃ and R₄ are the same or different and are each H, alkyl, alkylaryl oraryl.

The polyether-substituted amine may have a number-average molecularweight in the range from 500 to 5000, especially 800 to 3000 or 900 to1500.

The quaternizable, polyether-substituted amines are especially nitrogencompounds of the general formula Ia-1 or Ib-2

(R₁)(R₂)N-A-OCH(R₃)—CH(R₄)—O_(n)H  (Ia-1)

R₆—OCH(R₃)—CH(R₄)—OCH(R₃)—CH(R₄)—N(R₁)(R₂)  (Ib-2)

in whichR₁ and R₂ are the same or different and are each alkyl, alkenyl,hydroxyalkyl, hydroxyalkenyl, aminoalkyl or aminoalkenyl, or R₁ and R₂together are alkylene, oxyalkylene or aminoalkylene;R₃ and R₄ are the same or different and are each H, alkyl, alkylaryl oraryl:R₆ is alkyl, alkenyl, optionally mono- or polyunsaturated cycloalkyl,aryl, in each case optionally substituted, for example by at least onehydroxyl radical or alkyl radical, or interrupted by at least oneheteroatom;A is a straight-chain or branched alkylene radical optionallyinterrupted by one or more heteroatoms such as N, O and S; andn is an integer value from 1 to 50.

Particular mention should be made of those nitrogen compounds of theformulae Ia-1 and Ib-2 in which

R₁ and R₂ are the same or different and are each C₁-C₆-alkyl,hydroxy-C₁-C₆-alkyl, hydroxy-C₁-C₆-alkenyl, or amino-C₁-C₆-alkyl, or R₁and R₂ together form a C₂-C₆-alkylene, C₂-C₆-oxyalkylene orC₂-C₆-aminoalkylene radical;R₃ and R₄ are the same or different and are each H, C₁-C₆-alkyl orphenyl;R₆ is C₁-C₂₀-alkyl, for example C₁₀-C₂₀-, C₁₁-C₂₀- or C₁₂-C₂₀-alkyl oraryl or alkylaryl, where alkyl is especially C₁-C₂₀-;A is a straight-chain or branched C₂-C₆-alkylene radical optionallyinterrupted by one or more heteroatoms such as N, O and S; andn is an integer value from 1 to 30.

Particular mention should additionally be made of reaction products ofN,N-dimethylethanolamine and propylene oxide, as described in Synthesisexample 1 of WO 2013/064689. This reaction can also be performed withoutcatalysis or with an amine (for example imidazole) as a catalyst, asdescribed, for example, in M. Ionescu, Chemistry and Technology ofPolyols for Polyurethanes, 2005, ISBN 978-85957-501-7.

Nitrogen compounds of the general formula Ia-1 are preparable byalkoxylating an aminoalkanol of the general formula II

(R₁)(R₂)N-A-OH  (II)

in whichR₁, R₂ and A are each as defined abovewith an epoxide of the general formula III

in whichR₃ and R₄ are each as defined aboveto obtain an alkoxylated amine of the formula

(R₁)(R₂)N-A-OCH(R₃)—CH(R₄)—O—_(n)H  (Ia-1)

in which R₁ to R₄, A and n are each as defined above.

Nitrogen compounds of the general formula Ia-2 are preparable byalkoxylating an alcohol of the general formula V

R₆—OH  (V)

in whichR₆ is as defined above with an epoxide of the general formula III

in whichR₃ and R₄ are each as defined above to obtain a polyether of the formulaIb-1;

R₆—O└CH(R₃)—CH(R₄)—O_(n-1)CH(R₃)—CH(R₄)OH  (Ib-1)

in which R₃, R₄ and R₆, A and n are each as defined aboveandb) then aminating the polyether of the formula Ib-1 thus obtained withan amine of the general formula

NH(R₁)(R₂)  (VII)

in which R₁ and R₂ are each as defined aboveto obtain an amine of the formula Ib-2.

Starting compounds for preparation of the above polyether-substituted,quaternizable nitrogen compounds are thus:

1) alcohols,for example of the general formula V

R₆—OH  (V)

in which R₆ is alkyl, alkenyl, optionally mono- or polyunsaturatedcycloalkyl, aryl, in each case optionally substituted, for example by atleast one hydroxyl radical or alkyl radical, or interrupted by at leastone heteroatom;and2) amino alkanols,for example of the general formula II

(R₁)(R₂)N-A-OH  (II)

in whichR₁ and R₂ are the same or different and are each alkyl, alkenyl,hydroxyalkyl, hydroxyalkenyl, aminoalkyl or aminoalkenyl, or R₁ and R₂together are alkylene, oxyalkylene or aminoalkylene; andA is a straight-chain or branched alkylene or alkenylene radicaloptionally interrupted by one or more heteroatoms such as N, O and S.

A further suitable group of quaternizable amino alcohols that should bementioned is that of compounds selected from hydroxyalkyl-substitutedmono- or polyamines having at least one quaternizable, primary,secondary or tertiary amino group and at least one hydroxyl group whichcan be joined to a polyether radical.

The quaternizable nitrogen compound is especially selected fromhydroxyalkyl-substituted primary, secondary and especially tertiarymonoamines, and hydroxyalkyl-substituted primary, secondary andespecially tertiary diamines.

Examples of suitable “hydroxyalkyl-substituted mono- or polyamines” arethose provided with at least one hydroxyalkyl substituted, for example1, 2, 3, 4, 5 or 6 hydroxyalkyl substituted.

Examples of “hydroxyalkyl-substituted monoamines” include:N-hydroxyalkylmonoamines, N,N-dihydroxyalkylmonoamines andN,N,N-trihydroxyalkylmonoamines, where the hydroxyalkyl groups are thesame or different and are also as defined above. Hydroxyalkyl isespecially 2-hydroxyethyl, 3-hydroxypropyl or 4-hydroxybutyl.

For example, the following “hydroxyalkyl-substituted polyamines” andespecially “hydroxyalkyl-substituted diamines” may be mentioned:N-hydroxyalkylalkylenediamines, N,N-dihydroxyalkylalkyenediamines, wherethe hydroxyalkyl groups are the same or different and are also asdefined above. Hydroxyalkyl is especially 2-hydroxyethyl,3-hydroxypropyl or 4-hydroxybutyl; alkylene is especially ethylene,propylene or butylene.

Particular mention should be made of the following quaternizablenitrogen compounds:

NAME FORMULA Alcohols with a primary and secondary amine   ethanolamine

3-hydroxy-1-propylamine

diethanolamine

diisopropanolamine

N-(2- hydroxyethyl)ethylenediamine

Alcohols with a tertiary amine triethanolamine,(2,2^(I),2^(II)-nitrilotriethanol)

1-(3-hydroxypropyl)imidazole

tris(hydroxymethyl)amine

3-dimethylamino-1-propanol

3-diethylamino-1-propanol

2-dimethylamino-1-ethanol

4-diethylamino-1-butanol

For preparation of the polyether-substituted quaternizable compounds(Ia-1 and Ib-1), the procedure may be as follows:

a1) Proceeding from Amino Alcohols of the Formula II:

The amino alcohols of the general formula II can be alkoxylated in amanner known in principle to obtain alkoxylated amines of the generalformula Ia-1.

The performance of alkoxylations is known in principle to those skilledin the art. It is likewise known to those skilled in the art that thereaction conditions, especially the selection of the catalyst, caninfluence the molecular weight distribution of the alkoxylates.

For the alkoxylation, C₂-C₁₆-alkylene oxides are used, for exampleethylene oxide, propylene oxide or butylene oxide. Preference is givento the 1,2-alkylene oxides in each case.

The alkoxylation may be a base-catalyzed alkoxylation. For this purpose,the amino alcohols (II) can be admixed in a pressure reactor with alkalimetal hydroxides, preferably potassium hydroxide, or with alkali metalalkoxides, for example sodium methoxide. Water still present in themixture can be drawn off by means of reduced pressure (for example <100mbar) and/or increasing the temperature (30 to 150° C.). Thereafter, thealcohol is present in the form of the corresponding alkoxide. This isfollowed by inertization with inert gas (for example nitrogen) andstepwise addition of the alkylene oxide(s) at temperatures of 60 to 180°C. up to a pressure of max. 10 bar. At the end of the reaction, thecatalyst can be neutralized by adding acid (e.g. acetic acid orphosphoric acid) and can be filtered off if required. The basic catalystcan also be neutralized by addition of commercial magnesium silicates,which are subsequently filtered off. Optionally, the alkoxylation canalso be performed in the presence of a solvent. This may be, forexample, toluene, xylene, dimethylformamide or ethylene carbonate.

The alkoxylation of the amino alcohols can also be undertaken by meansof other methods, for example by acid-catalyzed alkoxylation. Inaddition, it is possible to use, for example, double hydroxide days, asdescribed in DE 43 25 237 A1, or it is possible to use double metalcyanide catalysts (DMC catalysts). Suitable DMC catalysts are disclosed,for example, in DE 102 43 361 A1, especially paragraphs [0029] to [0041]and the literature cited therein. For example, it is possible to usecatalysts of the Zn—Co type. To perform the reaction, the amino alcoholcan be admixed with the catalyst, and the mixture dewatered as describedabove and reacted with the alkylene oxides as described. Typically notmore than 1000 ppm of catalyst based on the mixture are used, and thecatalyst can remain in the product owing to this small amount. Theamount of catalyst may generally be less than 1000 ppm, for example 250ppm or less.

The alkoxylation can alternatively also be undertaken by reaction of thecompounds (IV) and (V) with cyclic carbonates, for example ethylenecarbonate.

a2) Proceeding from Alkanols of the Formula V:

As described in the above paragraph al) for amino alcohols (II), it isanalogously also possible to alkoxylate alkanols R₆OH in a manner knownin principle to polyethers (Ib-1). The polyethers thus obtained cansubsequently be converted to the corresponding polyether amines (Ib-2)by reductive amination with ammonia, primary amines or secondary amines(VII) by customary methods, in continuous or batchwise processes usinghydrogenation or amination catalysts customary therefor, for examplethose comprising catalytically active constituents based on the elementsNi, Co, Cu, Fe, Pd, Pt, Ru, Rh, Re, Al, Si, Ti, Zr, Nb, Mg, Zn, Ag, Au,Os, Ir, Cr, Mo, W or combinations of these elements with one another, incustomary amounts. The conversion can be performed without solvent or,in the case of high polyether viscosities, in the presence of a solvent,preferably in the presence of branched aliphatics, for exampleisododecane. The amine component (VII) is generally used here in excess,for example in a 2- to 100-fold excess, preferably a 10- to 80-foldexcess. The reaction is conducted at pressures of 10 to 600 bar over aperiod of 10 minutes to 10 hours. After cooling, the catalyst is removedby filtering, excess amine component (VII) is evaporated and the waterof reaction is distilled off azeotropically or under a gentle nitrogenstream.

Should the resulting polyether amine (Ib-2) have primary or secondaryamine functionalities (R₁ and/or R₂ is H), it can subsequently beconverted to a polyether amine having a tertiary amine function (R₁ andR₂ not H). The alkylation can be effected in a manner known in principleby reaction with alkylating agents. Any alkylating agents are suitablein principle, for example alkyl halides, alkylaryl halides, dialkylsulfates, alkylene oxides, optionally in combination with acid;aliphatic or aromatic carboxylic esters, such as dialkyl carboxylates inparticular; alkanoates; cyclic nonaromatic or aromatic carboxylicesters; dialkyl carbonates; and mixtures thereof. The conversions to thetertiary polyether amine can also take place through reductive aminationby reaction with a carbonyl compound, for example formaldehyde, in thepresence of a reducing agent. Suitable reducing agents are formic acidor hydrogen in the presence of a suitable heterogeneous or homogeneoushydrogenation catalyst. The reactions can be performed without solventor in the presence of solvents. Suitable solvents are, for example, H₂O,alkanols such as methanol or ethanol, or 2-ethylhexanol, aromaticsolvents such as toluene, xylene or solvent mixtures from the Solvessoseries, or aliphatic solvents, especially mixtures of branched aliphaticsolvents. The reactions are conducted at temperatures of 10° C. to 300°C. at pressures of 1 to 600 bar over a period of 10 minutes to 10 h. Thereducing agent is used here at least stoichiometrically, preferably inexcess, especially in a 2- to 10-fold excess.

The reaction product thus formed (polyether amine Ib-1 or Ib-2) cantheoretically be purified further, or the solvent can be removed.Usually, however, this is not absolutely necessary, and so the reactionproduct can be transferred without further purification into the nextsynthesis step, the quaternization.

A3.3) Polyalkene-substituted Amines Having at Least One Tertiary,Quaternizable Nitrogen Group

Further suitable quaternizable nitrogen compounds arepolyalkene-substituted amines having at least one tertiary nitrogengroup. This group of compounds is likewise known and is described, forexample, in WO 2008/060888 or US 2008/0113890 and the further prior artcited therein, which is hereby explicitly incorporated by reference.

Such polyalkene-substituted amines having at least one tertiary aminogroup are derivable from an olefin polymer and an amine such as ammonia,monoamines, polyamines or mixtures thereof. They can be prepared by amultitude of processes, for example the following processes cited by wayof example:

A process for preparing a polyalkene-substituted amine comprises thereaction of a halogenated olefin polymer with an amine, as described inU.S. Pat. Nos. 3,275,554, 3,438,757, 3,454,555, 3,565,804, 3,755,433 and3,822,289.

A further process for preparing a polyalkene-substituted amine comprisesthe reaction of a hydroformylated olefin with a polyamine andhydrogenation of the reaction product, as described in U.S. Pat. Nos.5,567,845 and 5,496,383.

A further process for preparing a polyalkene-substituted amine comprisesthe conversion of a polyalkene with the aid of a conventionalepoxidizing reagent with or without catalyst to the correspondingepoxide and the conversion of the epoxide to the polyalkene-substitutedamine by reaction with ammonia or an amine under the conditions ofreductive amination, as described in U.S. Pat. No. 5,350,429.

A further process for preparing a polyalkene-substituted amine comprisesthe hydrogenation of a β-amino nitrile which has been prepared byreaction of an amine with a nitrile, as described in U.S. Pat. No.5,492,641.

A further process for preparing a polyalkene-substituted amine compriseshydroformylation of a polybutene or polyisobutylene with a catalyst,such as rhodium or cobalt, in the presence of CO and hydrogen atelevated pressures and temperatures, as described in U.S. Pat. No.4,832,702.

In one embodiment of the invention, the polyalkenes used for thepreparation are derived from olefin polymers. The olefin polymers maycomprise homopolymers and co-polymers of polymerizable olefin monomershaving 2 to about 16 carbon atoms, 2 to about 6 carbon atoms or 2 toabout 4 carbon atoms.

Interpolymers are those in which two or more olefin monomers areinterpolymerized by known conventional methods, giving polyalkeneshaving units derived from each of the two or more olefin monomers withintheir structure. Thus, “interpolymers” comprise copolymers, terpolymersand tetrapolymers.

“Polyalkenes”, from which the polyalkene-substituted amines are derived,are conventionally frequently also referred to as “polyolefins”.

The olefin monomers from which the olefin polymers are derived arepolymerizable olefin monomers having one or more ethylenicallyunsaturated groups (i.e. >C═C<); in other words, they are monoolefinicmonomers such as ethylene, propylene, 1-butene, isobutene(2-methyl-1-butene), 1-octene, or polyolefinic monomers (usuallydiolefinic monomers) such as 1,3-butadiene and isoprene.

The olefin monomers are usually polymerizable terminal olefins, i.e.olefins having the >C═CH₂ group in their structure. However, it is alsopossible to use polymerizable internal olefin monomers characterized bygroups of the formula >C—C═C—C<.

Specific examples of terminal and internal olefin monomers which can beused to prepare the polyalkenes by conventional methods are: ethylene,propylene, the butenes (butylene), especially 1-butene, 2-butene andisobutylene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene,1-decene, 2-pentene, propylene tetramer, diisobutylene, isobutylenetrimer, 1,2-butadiene, 1,3-butadiene, 1,2-pentadiene, 1,3-pentadiene,1,4-pentadiene, isoprene, 1,5-hexadiene, 2-methyl-5-propyl-1-hexene,3-pentene, 4-octene and 3,3-dimethyl-1-pentene.

In another embodiment, the olefin polymer is preparable bypolymerization of a C₄ refinery stream having a butene content of about35 to about 75 percent by weight and an isobutene content of about 30 toabout 60 percent by weight in the presence of a Lewis acid catalyst suchas aluminum trichloride or boron trifluoride. These polybutenestypically comprise predominantly (more than about 80% of all the repeatunits) repeat isobutene units of the (—CH₂—C(CH₃)₂—) type.

In a further embodiment, the polyalkene substituent of thepolyalkene-substituted amine is derived from a polyisobutylene.

In another embodiment, the amines which can be used to form thepolyalkene-substituted amine comprise ammonia, monoamines, polyamines ormixtures thereof, including mixtures of various monoamines, mixtures ofvarious polyamines and mixtures of monoamines and polyamines (thediamines). The amines comprise aliphatic, aromatic, heterocyclic andcarbocyclic amines. Monoamines and polyamines are characterized by thepresence in their structure of at least one HN< group. The amines may bealiphatic, cycloaliphatic, aromatic or heterocyclic.

The monoamines are generally substituted by a hydrocarbyl group having 1to 50 carbon atoms. These hydrocarbyl groups may especially be aliphaticand free of acetylenically unsaturated groups and have 1 to about 30carbon atoms. Particular mention should be made of saturated aliphatichydrocarbyl radicals having 1 to 30 carbon atoms.

In a further embodiment, the monoamines may have the formula HNR₁R₂where R₁ is a hydrocarbyl group having up to 30 carbon atoms and R₂ ishydrogen or a hydrocarbyl group having up to about 30 carbon atoms.Examples of suitable monoamines are methylamine, ethylamine,diethylamine, 2-ethylhexylamine, di(2-ethylhexyl)amine, n-butylamine,di-n-butylamine, allylamine, isobutylamine, cocoamine, stearylamine,laurylamine, methyllaurylamines and oleylamine.

Aromatic monoamines are those monoamines in which a carbon atom in thearomatic ring structure is bonded directly to the amine nitrogen atom.The aromatic ring will usually be a monocyclic aromatic ring (i.e.derived from benzene), but may include fused aromatic rings, especiallythose derived from naphthalene. Examples of aromatic monoamines areaniline, di(para-methylphenyl)amine, naphthylamine, N-(n-butyl)aniline.Examples of aliphatic-substituted, cycloaliphatic-substituted andheterocyclic-substituted aromatic monoamines are: para-dodecylaniline,cyclohexyl-substituted naphthylamine and thienyl-substituted aniline.

Hydroxylamines are likewise suitable monoamines. Compounds of this kindare the hydroxyhydrocarbyl-substituted analogs of the aforementionedmonoamines.

In one embodiment, the hydroxy monoamines are those of the formulaHNR₃R₄ where R₃ is a hydroxyl-substituted alkyl group having up to about30 carbon atoms, and in one embodiment up to about 10 carbon atoms; andR₄ is a hydroxyl-substituted alkyl group having up to about 30 carbonatoms, hydrogen or a hydrocarbyl group having up to about 10 carbonatoms. Examples of hydroxyl-substituted monoamines include:ethanolamine, di-3-propanolamine, 4-hydroxybutylamine, diethanolamineand N-methyl-2-hydroxypropylamine.

In another embodiment, the amine of the polyalkene-substituted aminesmay be a polyamine. The polyamine may be aliphatic, cycloaliphatic,heterocyclic or aromatic. Examples of the polyamines include:alkylenepolyamines, hydroxyl group-comprising polyamines, arylpolyamines and heterocyclic polyamines.

The alkylenepolyamines comprise those of the following formula:

HN(R⁵)-(alkylene-N(R⁵))_(n)—(R⁵)

in which n is in the range from 1 to about 10 and, for example, in therange from 2 to about 7, or from 2 to about 5, and the “alkylene” grouphas 1 to about 10 carbon atoms, for example 2 to about 6, or 2 to about4 carbon atoms;the R⁵ radicals are each independently hydrogen, an aliphatic group, ahydroxyl- or amine-substituted aliphatic group of up to about 30 carbonatoms in each case. Typically, R⁵ is H or lower alkyl (an alkyl grouphaving 1 to about 5 carbon atoms), especially H. Alkylenepolyamines ofthis kind include: methylenepolyamines, ethylenepolyamines,butylenepolyamines, propylenepolyamines, pentylenepolyamines,hexylenepolyamines and heptylenepolyamines. The higher homologs of suchamines and related aminoalkyl-substituted piperazines are likewiseincluded.

Specific alkylenepolyamines for preparation of thepolyalkene-substituted amines are the following: ethylenediamine,diethylenetriamine, triethylenetetramine, tetraethylenepentamine,propylenediamine, 3-dimethylaminopropylamine, trimethylenediamine,hexamethylenediamine, decamethylenediamine, octamethylenediamine,di(heptamethylene)triamine, tripropylenetetramine,pentaethylenehexamine, di(trimethylenetriamine),N-(2-aminoethyl)piperazine and 1,4-bis(2-aminoethyl)piperazine.

Ethylenepolyamines, such as those mentioned above, are particularlysuitable for reasons of cost and effectiveness. Polyamines of this kindare described in detail in the chapter “Diamine und höhere Amine”[Diamines and Higher Amines] in Encyclopedia of Chemical Technology,second edition, Kirk-Othmer, volume 7, pages 27-39, Inter-sciencePublishers, division of John Wiley & Sons, 1965. Compounds of this kindare most conveniently prepared by the reaction of an alkylene chloridewith ammonia or by reaction of an ethyleneimine with a ring-openingreagent such as ammonia. These reactions lead to preparation of complexmixtures of alkylenepolyamines, including cyclic condensation productssuch as piperazines.

Other suitable types of polyamine mixtures are the products which areformed as residue by stripping the above-described polyamine mixturesand are frequently referred to as “polyamine bottoms”. In general,alkylenepolyamine bottom products are those which comprise less thantwo, usually less than 1%, by weight of material that boils below about200° C. A typical example of such ethylenepolyamine bottoms is that ofthe products designated “E 100” from Dow Chemical Company in Freeport,Tex. These alkylenepolyamine bottoms comprise cyclic condensationproducts such as piperazine and higher analogs of diethylenetriamine,triethylenetetramines and the like.

Hydroxyl group-comprising polyamines include:hydroxyalkylalkylenepolyamines having one or more hydroxyalkylsubstituents on the nitrogen atoms. Polyamines of this kind can beprepared by reacting the above-described alkylenepolyamines with one ormore alkylene oxides (e.g. ethylene oxide, propylene oxide and butyleneoxide). Similar alkylene oxide-alkanolamine reaction products may also,for example, be the products of the reaction of primary, secondary ortertiary alkanolamines with ethylene, propylene or higher epoxides in amolar ratio of 1:1 to 1:2. Reactant ratios and temperatures forperformance of such reactions are known to those skilled in the art.

In another embodiment, the hydroxyalkyl-substituted alkylenepolyaminemay be a compound in which the hydroxyalkyl group is a hydroxy-loweralkyl group, i.e. has fewer than eight carbon atoms. Examples of suchhydroxyalkyl-substituted polyamines includeN-(2-hydroxyethyl)ethylenediamine (also known as2-(2-aminoethylamino)ethanol), N,N-bis(2-hydroxyethyl)ethylenediamine,1-(2-hydroxyethyl)piperazine, monohydroxypropyl-substituteddiethylenetriamine, dihydroxypropyl-substituted tetraethylenepentamineand N-(3-hydroxybutyl)tetramethylenediamine.

Aryl polyamines are analogs of the abovementioned aromatic monoamines.Examples of aryl polyamines include:N,N′-di-n-butyl-para-phenylenediamine and bis(para-aminophenyl)methane.

Heterocyclic mono- and polyamines may comprise: aziridines, azetidines,azolidines, pyridines, pyrroles, indoles, piperidines, imidazoles,piperazines, isoindoles, purines, morpholines, thiomorpholines,N-aminoalkylmorpholines, N-aminoalkylthiomorpholines,N-aminoalkylpiperazines, N,N′-diaminoalkylpiperazines, azepines,azocines, azonines, azecines and tetra-, di- and perhydro derivatives ofeach of the above compounds and mixtures of two or more of theseheterocyclic amines. Typical heterocyclic amines are saturated 5- and6-membered heterocyclic amines having only nitrogen, oxygen and/orsulfur in the heterocycle, especially piperidines, piperazines,thiomorpholines, morpholines, pyrrolidines and the like. Piperidine,aminoalkyl-substituted piperidines, piperazine, aminoalkyl-substitutedpiperazines, morpholine, aminoalkyl-substituted morpholines, pyrrolidineand aminoalkyl-substituted pyrrolidines are particularly preferred.Usually, the aminoalkyl substituents are bonded to a nitrogen atom whichis part of the heterocycle.

Specific examples of such heterocyclic amines includeN-aminopropylmorpholine. N-aminoethylpiperazine andN,N′-diaminoethylpiperazine. Hydroxyheterocyclic polyamines are alsosuitable. Examples include: N-(2-hydroxyethyl)cyclohexylamine,3-hydroxycyclopentylamine, para-hydroxyaniline andN-hydroxyethylpiperazine.

Examples of polyalkene-substituted amines are as follows:poly(propylene)amine, poly(butene)amine,N,N-dimethylpolyisobutyleneamines; polybutenemorpholines,N,N-poly(butene)ethylenediamine, N-poly(propylene)trimethylenediamine,N-poly(butene), diethylenetriamine,N′,N′-poly(butene)tetraethylenepentamine andN,N-dimethyl-N′-poly(propylene)-1,3-propylenediamine.

The number-average molecular weight of such polyalkene-substitutedamines is about 500 to about 5000, for example 1000 to about 1500 orabout 500 to about 3000.

Any of the abovementioned polyalkene-substituted amines which aresecondary or primary amines can be alkylated to tertiary amines withalkylating agents which are also known as quaternizing agents, such asdialkyl sulfates, alkyl halides, hydrocarbyl-substituted carbonates;hydrocarbyl epoxides in combination with an acid and mixtures thereof.If particular quaternizing agents, such as alkyl halides or dialkylsulfates, are used, it may be necessary to provide a base or basiccompositions, such as sodium carbonate or sodium hydroxide, to give thefree tertiary amine form. Primary amines require two equivalents ofalkylating agent and two equivalents of base to obtain a tertiary amine.In another embodiment, the alkylation of primary amines can frequentlybe conducted in four successive steps, first a treatment with thealkylating agent, followed by a second treatment with a base and thenrepetition of the two steps. In another embodiment, the alkylation of aprimary amine will be effected in one step, for example using two molesof alkyl halide in the presence of an excess of heterogeneous base, suchas sodium carbonate. The polyamine can be exhaustively or partiallyalkylated in a manner known per se.

In another embodiment, the alkylation of primary amines and secondaryamines to tertiary amines can be effected with epoxides. Unlike the useof the alkyl halides, no treatment with base is required in the case ofuse of an epoxide to obtain the free amine. Typically, in the case ofalkylation of amines with epoxides, at least one mole of epoxide is usedfor each hydrogen atom in the amine. In the alkylation to give thetertiary amine with an epoxide, neither additional acid nor base isrequired.

Particular preference is additionally given topolyisobutenedimethylamine obtainable by hydroformylating polyisobutene(Mn 1000) and subsequent reductive amination with dimethylamine; seeExample B of WO 2008/060888.

A3.4) Reaction Products of a Hydrocarbyl-Substituted Acylating Agent anda Compound Comprising a Nitrogen or Oxygen Atom and AdditionallyComprising at Least One Quaternizable Amino Group

Compounds of this kind are described, for example, in the applicant'sWO2013/000997, which is hereby explicitly incorporated by reference.

Suitable hydrocarbyl-substituted polycarboxylic acid compounds, orhydrocarbyl-substituted acylating agents, include:

The polycarboxylic acid compounds used are aliphatic di- or polybasic(for example tri- or tetrabasic), especially from di-, tri- ortetracarboxylic acids and analogs thereof, such as anhydrides or loweralkyl esters (partially or completely esterified), and is optionallysubstituted by one or more (for example 2 or 3), especially a long-chainalkyl radical and/or a high molecular weight hydrocarbyl radical,especially a polyalkylene radical. Examples are C₃-C₁₀ polycarboxylicacids, such as the dicarboxylic acids malonic acid, succinic acid,glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid andsebacic acid, and the branched analogs thereof; and the tricarboxylicacid citric acid; and anhydrides or lower alkyl esters thereof. Thepolycarboxylic acid compounds can also be obtained from thecorresponding monounsaturated acids and addition of at least onelong-chain alkyl radical and/or high molecular weight hydrocarbylradical. Examples of suitable monounsaturated acids are fumaric acid,maleic acid, itaconic acid.

The hydrophobic “long-chain” or “high molecular weight” hydrocarbylradical which ensures sufficient solubility of the quaternized productin the fuel has a number-average molecular weight (M_(n)) of 85 to 20000, for example 113 to 10 000, or 200 to 10 000 or 350 to 5000, forexample 350 to 3000, 500 to 2500, 700 to 2500, or 800 to 1500. Typicalhydrophobic hydrocarbyl radicals include polypropenyl, polybutenyl andpolyisobutenyl radicals, for example with a number-average molecularweight M_(n) of 3500 to 5000, 350 to 3000, 500 to 2500, 700 to 2500 and800 to 1500.

Suitable hydrocarbyl-substituted compounds are described, for example,in DE 43 19 672 and WO 2008/138838.

Suitable hydrocarbyl-substituted polycarboxylic acid compounds alsocomprise polymeric, especially dimeric, forms of suchhydrocarbyl-substituted polycarboxylic acid compounds. Dimeric formscomprise, for example, two acid anhydride groups which can be reactedindependently with the quaternizable nitrogen compound in thepreparation process according to the invention.

The quaternizable nitrogen compounds reactive with the abovepolycarboxylic acid compound are selected from

-   a) hydroxyalkyl-substituted mono- or polyamines having at least one    quaternized (e.g. choline) or quaternizable primary, secondary or    tertiary amino group;-   b) straight-chain or branched, cyclic, heterocyclic, aromatic or    nonaromatic polyamines having at least one primary or secondary    (anhydride-reactive) amino group and having at least one quaternized    or quaternizable primary, secondary or tertiary amino group;-   c) piperazines.

The quaternizable nitrogen compounds are especially selected from

-   d) hydroxyalkyl-substituted primary, secondary, tertiary or    quaternary monoamines and hydroxyalkyl-substituted primary,    secondary, tertiary or quaternary diamines;-   e) straight-chain or branched aliphatic diamines having two primary    amino groups; di- or polyamines having at least one primary and at    least one secondary amino group; di- or polyamines having at least    one primary and at least one tertiary amino group; di- or polyamines    having at least one primary and at least one quaternary amino group;    aromatic carbocyclic diamines having two primary amino groups;    aromatic heterocyclic polyamines having two primary amino groups;    aromatic or nonaromatic heterocycles having one primary and one    tertiary amino group.

Examples of suitable “hydroxyalkyl-substituted mono- or polyamines” arethose provided with at least one hydroxyalkyl substituted, for example1, 2, 3, 4, 5 or 6 hydroxyalkyl substituted.

Examples of “hydroxyalkyl-substituted monoamines” include:N-hydroxyalkylmonoamines, N,N-dihydroxyalkylmonoamines andN,N,N-trihydroxyalkylmonoamines, where the hydroxyalkyl groups are thesame or different and are also as defined above. Hydroxyalkyl isespecially 2-hydroxyethyl, 3-hydroxypropyl or 4-hydroxybutyl.

For example, the following “hydroxyalkyl-substituted polyamines” andespecially “hydroxyalkyl-substituted diamines” may be mentioned:N-hydroxyalkylalkylenediamines, N,N-dihydroxyalkylalkylenediamines,where the hydroxyalkyl groups are the same or different and are also asdefined above. Hydroxyalkyl is especially 2-hydroxyethyl,3-hydroxypropyl or 4-hydroxybutyl; alkylene is especially ethylene,propylene or butylene.

Suitable “diamines” are alkylenediamines, and the N-alkyl-substitutedanalogs thereof, such as N-monoalkylated alkylenediamines and the N,N-or N,N′-dialkylated alkylenediamines. Alkylene is especiallystraight-chain or branched C₁₋₇- or C₁₋₄-alkylene as defined above.Alkyl is especially C₁₋₄-alkyl as defined above. Examples are especiallyethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine,1,4-butylenediamine and isomers thereof, pentanediamine and isomersthereof, hexanediamine and isomers thereof, heptanediamine and isomersthereof, and singly or multiply, for example singly or doubly,C₁-C₄-alkylated, for example methylated, derivatives of theaforementioned diamine compounds such as 3-dimethylamino-1-propylamine(DMAPA), N,N-diethylaminopropylamine and N,N-dimethylaminoethylamine.

Suitable straight-chain “polyamines” are, for example,dialkylenetriamine, trialkylenetetramine, tetraalkyenepentamine,pentaalkylenehexamine, and the N-alkyl-substituted analogs thereof, suchas N-monoalkylated and the N,N- or N,N′-dialkylated alkylenepolyamines.Alkylene is especially straight-chain or branched C₁₋₇ or C₁₋₄-alkyleneas defined above. Alkyl is especially C₁₋₄-alkyl as defined above.

Examples are especially diethylenetriamine, triethylenetetramine,tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine,tripropylenetetramine, tetrapropylenepentamine, pentapropylenehexamine,dibutylenetriamine, tributylenetetramine, tetrabutylenepentamine,pentabutylenehexamine; and the N,N-dialkyl derivatives thereof,especially the N,N-di-C₁₋₄-alkyl derivatives thereof. Examples include:N,N-dimethyldimethylenetriamine, N,N-diethyldimethylenetriamine,N,N-dipropyldimethylenetriamine, N,N-dimethyldiethylene-1,2-triamine,N,N-diethyldiethylene-1,2-triamine, N,N-dipropyldiethylene-1,2-triamine,N,N-dimethyldipropylene-1,3-triamine (i.e. DMAPAPA),N,N-diethyldipropylene-1,3-triamine,N,N-dipropyldipropylene-1,3-triamine,N,N-dimethyldibutylene-1,4-triamine, N,N-diethyldibutylene-1,4-triamine,N,N-dipropyldibutylene-1,4-triamine,N,N-dimethyldipentylene-1,5-triamine,N,N-diethyldipentylene-1,5-triamine,N,N-dipropyldipentylene-1,5-triamine,N,N-dimethyldihexylene-1,6-triamine, N,N-diethyldihexylene-1,6-triamineand N,N-dipropyldihexylene-1,6-triamine.

“Aromatic carbocyclic diamines” having two primary amino groups are thediamino-substituted derivatives of benzene, biphenyl, naphthalene,tetrahydronaphthalene, fluorene, indene and phenanthrene.

“Aromatic or nonaromatic heterocyclic polyamines” having two primaryamino groups are the derivatives, substituted by two amino groups, ofthe following heterocycles:

-   -   5- or 6-membered, saturated or monounsaturated heterocycles        comprising one to two nitrogen atoms and/or one oxygen or sulfur        atom or one or two oxygen and/or sulfur atoms as ring members,        for example tetrahydrofuran, pyrrolidine, isoxazolidine,        isothiazolidine, pyrazolidine, oxazolidine, thiazolidine,        imidazolidine, pyrroline, piperidine, piperidinyl, 1,3-dioxane,        tetrahydropyran, hexahydropyridazine, hexahydropyrimidine,        piperazine;    -   5-membered aromatic heterocycles comprising, in addition to        carbon atoms, one, two or three nitrogen atoms or one or two        nitrogen atoms and one sulfur or oxygen atom as ring members,        for example furan, thiane, pyrrole, pyrazole, oxazole, thiazole,        imidazole and 1,3,4-triazole; isoxazole, isothiazole,        thiadiazole, oxadiazole;    -   6-membered heterocycles comprising, in addition to carbon atoms,        one or two, or one, two or three, nitrogen atoms as ring        members, for example pyridinyl, pyridazine, pyrimidine,        pyrazinyl, 1,2,4-triazine, 1,3,5-triazin-2-yl.

“Aromatic or nonaromatic heterocycles having one primary and onetertiary amino group” are, for example, the abovementionedN-heterocycles which are aminoalkylated on at least one ring nitrogenatom, and especially bear an amino-C₁₋₄-alkyl group.

“Aromatic or nonaromatic heterocycles having one tertiary amino groupand one hydroxyalkyl group” are, for example, the abovementionedN-heterocycles which are hydroxyalkylated on at least one ring nitrogenatom, and especially bear a hydroxy-C₁₋₄-alkyl group.

Particular mention should be made especially of the following groups ofindividual classes of quaternizable nitrogen compounds:

Group 1:

NAME FORMULA Diamines with primary second nitrogen atom ethylenediamine

1,2-propylenediamine

1,3-propylenediamine

Isomeric butylenediamines, for example

1,5-pentylenediamine

Isomeric pentanediamines, for example

Isomeric hexanediamines, for example

Isomeric heptanediamines, for example

Di- and polyamines with a secondary second nitrogen atomdiethylenetriamine (DETA)

dipropylenetriamine (DPTA), 3,3′-iminobis(N,N- dimethylpropylamine)

triethylenetetramine (TETA)

tetraethylenepentamine (TEPA)

pentaethylenehexamine

N-methyl-3-amino-1-propylamine

bishexamethylenetriamine

Aromatics Diaminobenzenes, for example

Diaminopyridines, for example

Group 2:

NAME FORMULA Heterocycles 1-(3-aminopropyl)imidazole

4-(3-aminopropyl)morpholine

1-(2-aminoethylpiperidine)

2-(1-piperazinyl)ethylamine (AEP)

N-methylpiperazine

Amines with a tertiary second nitrogen atom3,3-diamino-N-methyldipropylamine

3-dimethylamino-1-propylamine (DMAPA)

N,N-diethylaminopropylamine

N,N-dimethylaminoethylamine

NAME FORMULA Alcohols with a primary and secondary amine ethanolamine

3-hydroxy-1-propylamine

diethanolamine

diisopropanolamine

N-(2-hydroxyethyl)ethylenediamine

Alcohols with a tertiary amine triethanolamine, (2,2^(I),2^(II)-nitrilotriethanol)

1-(3-hydroxypropyl)imidazole

tris(hydroxymethyl)amine

3-dimethylamino-1-propanol

3-diethylamino-1-propanol

2-dimethylamino-1-ethanol

4-diethylamino-1-butanol

The hydrocarbyl-substituted polycarboxylic acid compound can be reactedwith the quaternizable nitrogen compound under thermally controlledconditions, such that there is essentially no condensation reaction.More particularly, no formation of water of reaction is observed in thatcase. More particularly, such a reaction is effected at a temperature inthe range from 10 to 80° C. especially 20 to 60° C. or 30 to 50° C. Thereaction time may be in the range from a few minutes or a few hours, forexample about 1 minute up to about 10 hours. The reaction can beeffected at pressure at about 0.1 to 2 atm, but especially at aboutstandard pressure. For example, an inert gas atmosphere is appropriate,for example nitrogen.

More particularly, the reaction can also be effected at elevatedtemperatures which promote condensation, for example in the range from90 to 100° C. or 100 to 170° C. The reaction time may be in the regionof a few minutes or a few hours, for example about 1 minute up to about10 hours. The reaction can be effected at pressure at about 0.1 to 2atm, but especially at about standard pressure.

The reactants are initially charged especially in about equimolaramounts; optionally, a small molar excess of the polycarboxylic acidcompound, for example a 0.05- to 0.5-fold, for example a 0.1- to0.3-fold, excess, is desirable. If required, the reactants can beinitially charged in a suitable inert organic aliphatic or aromaticsolvent or a mixture thereof. Typical examples are, for example,solvents of the Solvesso series, toluene or xylene. The solvent can alsoserve, for example, to remove water of condensation azeotropically fromthe reaction mixture. More particularly, however, the reactions areperformed without solvent.

The reaction product thus formed can theoretically be purified further,or the solvent can be removed. Usually, however, this is not absolutelynecessary, such that the reaction product can be transferred withoutfurther purification into the next synthesis step, the quaternization.

Particular mention should be made of the condensation product ofpolyisobutylenesuccinic anhydride (Glissopal® SA from BASF, preparedfrom polyisobutene (Mn 1000) and maleic anhydride in a known manner) andN,N-dimethyl-1,3-diaminopropane (CAS 109-55-7), see Preparation example1 of WO 2013/000997.

A4) Quaternizing Agents:

In another particular embodiment, the at least one quaternizabletertiary nitrogen atom is quaternized with at least one quaternizingagent selected from epoxides, especially hydrocarbyl epoxides.

where the R_(d) radicals present therein are the same or different andare each H or a hydrocarbyl radical, where the hydrocarbyl radical hasat least 1 to 10 carbon atoms. More particularly, these are aliphatic oraromatic radicals, for example linear or branched C₁₋₁₀-alkyl radicals,or aromatic radicals, such as phenyl or C₁₋₄-alkylphenyl.

Examples of suitable hydrocarbyl epoxides include aliphatic and aromaticalkylene oxides such as, more particularly, C₂₋₁₂-alkylene oxides suchas ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butyleneoxide, 2-methyl-1,2-propene oxide (isobutene oxide), 1,2-pentene oxide,2,3-pentene oxide, 2-methyl-1,2-butene oxide, 3-methyl-1,2-butene oxide,1,2-hexene oxide, 2,3-hexene oxide, 3,4-hexene oxide,2-methyl-1,2-pentene oxide, 2-ethyl-1,2-butene oxide,3-methyl-1,2-pentene oxide, 1,2-decene oxide, 1,2-dodecene oxide or4-methyl-1,2-pentene oxide; and aromatic-substituted ethylene oxidessuch as optionally substituted styrene oxide, especially styrene oxideor 4-methylstyrene oxide.

In the case of use of epoxides as quaternizing agents, these are used inthe presence of free acids, especially in the presence of freehydrocarbyl-substituted unsaturated, especially saturated, optionallysubstituted, especially unsubstituted, protic acids such as, moreparticularly, hydrocarbyl-substituted dicarboxylic acids, especiallyhydrocarbyl-substituted C₃-C₂₆ or C₃-C₁₂ dicarboxylic acids, especiallyunsubstituted saturated C₃-C₆ dicarboxylic acid.

Suitable dicarboxylic acids here are saturated acids such as malonicacid, succinic acid, glutaric acid, adipic acid, pimelic acid, subericacid, azelaic acid, sebacic acid, undecanedioic acid and dodecanedioicacid, or higher molecular weight acids, such as tetra-, hexa- oroctadecanedioic acid; substituted acids, such as malic acid,α-ketoglutaric acid, oxaloacetic acid; glutamic acid; aspartic acid; andunsaturated acids, such as maleic acid and fumaric acid; such as, moreparticularly, malonic acid, succinic acid, glutaric acid, adipic acidand pimelic acid.

Additionally suitable are aromatic dicarboxylic acids, for examplephthalic acid.

If required or desired, it is also possible to usehydrocarbyl-substituted dicarboxylic acids in their anhydride form. Forthe quaternization, the ring opening of the anhydride is then broughtabout by addition of water.

Further configurations relating to hydrocarbyl-substituted dicarboxylicacids:

The hydrocarbyl-substituted dicarboxylic acids can be prepared byhydrolysis of the corresponding hydrocarbyl-substituted dicarboxylicanhydrides in a manner known in principle, as described, for example, inDE 2443537. The hydrolysis is preferably conducted with stoichiometricamounts of water at temperatures of 50 to 150° C., but it is alsopossible to use an excess of water. The hydrolysis can be conductedwithout solvent or in the presence of an inert solvent. Typical examplesare, for example, solvents from the Solvesso series, toluene, xylene orstraight-chain and branched saturated hydrocarbons such as paraffins ornaphthenes. The solvent can be removed after the hydrolysis, butpreferably remains, and is used as solvent or cosolvent for thesubsequent quaternization.

Preferred hydrocarbyl-substituted dicarboxylic anhydrides arehydrocarbyl-substituted succinic anhydrides, as sold, for example, byPentagon: n-dodecenylsuccinic anhydride CAS 19780-11-1,n-octadecenylsuccinic anhydride CAS 28777-98-2, i-octadecenylsuccinicanhydride CAS 28777-98-2, i-hexadecenylsuccinicanhydride/i-octadecenylsuccinic anhydride CAS 32072-96-1 & 28777-98-2,n-octenylsuccinic anhydride CAS 26680-54-6, tetrapropenylsuccinicanhydride CAS 26544-38-7.

Additionally preferred is polyisobutenesuccinic anhydride (PIBSA). Thepreparation of PIBSA from polyisobutene (PIB) and maleic anhydride (MA)is known in principle and leads to a mixture of PIBSA and bismaleatedPIBSA (BM PIBSA, please see scheme 1 below), which is generally notpurified but processed further as it is. The ratio of the two componentsto one another can be reported as the bismaleation level (BML). The BMLis known in principle (see U.S. Pat. No. 5,883,196) and is determined asdescribed in U.S. Pat. No. 5,883,196.

Especially preferred is PIBSA having a bismaleation level of up to 30%,preferably up to 25% and more preferably up to 20%. In general, thebismaleation level is at least 2%, preferably at least 5% and morepreferably at least 10%. Controlled preparation is described, forexample, in U.S. Pat. No. 5,883,196. For the preparation,high-reactivity PIB (HR-PIB) having Mn in the range from 500 to 3000,for example 550 to 2500, 800 to 1200 or 900 to 1100 is particularlysuitable. Mn is determined by means of GPC as described in U.S. Pat. No.5,883,196. Particularly preferred PIBSA prepared from HR-PIB (Mn=1000)has hydrolysis numbers of 85-95 mg KOH/g.

A nonlimiting example of a particularly suitable PIBSA is Glissopal® SAF from BASF, prepared from HR-PIB (Mn=1000) having a bismaleation levelof 15% and a hydrolysis number of 90 mg KOH/g.

It is also conceivable, albeit less preferable, to react theabovementioned hydrocarbyl-substituted dicarboxylic anhydrides not withwater but with an alcohol, preferably a monoalcohol, more preferably analcohol, or an amine to give the corresponding monoester or monoamide ofthe hydrocarbyl-substituted dicarboxylic acids. What is important isthat one acid function remains in the molecule in the case of such areaction.

If the quaternization is conducted in the presence of an alcohol,preference is given to using the same alcohol for such a reaction of thehydrocarbyl-substituted dicarboxylic anhydrides as that used as solventin the quaternization, i.e. preferably 2-ethylhexanol or2-propylheptanol, or else butyldiglycol, butylglycol,methoxypropoxypropanol or butoxydipropanol.

Such an alcoholysis is preferably conducted with stoichiometric amountsof alcohol or amine at temperatures of 50 to 150° C., but it is alsopossible to use an excess of alcohol or amine, preferably alcohol. Inthat case, the latter appropriately remains in the reaction mixture andserves as solvent in the subsequent quaternization.

A5) Preparation of Inventive Additives: a) Quaternization

The quaternization with an epoxide of the formula (4) is based inprinciple on known processes. If the boiling temperature of onecomponent of the reaction mixture, especially of the epoxide, atstandard pressure is above the reaction temperature, the reaction isappropriately conducted in an autoclave.

For example, in an autoclave, a solution of the tertiary amine isadmixed with the organic hydrocarbyl-substituted dicarboxylic acid (forexample polyisobutenesuccinic acid) in the required, approximatelystoichiometric amounts. For every equivalent of quaternizable tertiarynitrogen atom, it is possible to use, for example, 0.1 to 2.0, 0.2 to1.5 or 0.5 to 1.25 equivalents of dicarboxylic acid. More particularly,however, approximately molar proportions of the dicarboxylic acid areused. This is followed by sufficient purging with N₂ and establishmentof a suitable supply pressure, and by metered addition of the epoxide(e.g. propylene oxide) in the required stoichiometric amounts at atemperature between 20° C. and 180° C. For every equivalent ofquaternizable tertiary nitrogen atom, it is possible to use, forexample, 0.1 to 4.0, 0.2 to 3 or 0.5 to 2 equivalents of epoxide. Moreparticularly, however, about 1 to 2 equivalents of epoxide are used inrelation to the tertiary amine, in order to fully quaternize thetertiary amine group. More particularly, it is also possible to use amolar excess of alkylene oxide, as a result of which the free carboxylgroup of the dicarboxylic acid is partly or fully esterified.Subsequently, over a suitably long period of a few minutes to about 24hours, for example about 10 h, stirring is continued at a temperaturebetween 20° C. and 180° C. (e.g. 50° C.), the mixture is cooled, forexample to about 20 to 50° C. and purged with N₂, and the reactor isemptied.

The reaction can be effected at a pressure of about 0.1 to 20 bar, forexample 1 to 10 or 1.5 to 5 bar. The reaction can however also beeffected under standard pressure. More particularly, an inert gasatmosphere, for example nitrogen, is appropriate.

If required, the reactants can be initially charged for thequaternization in a suitable inert organic aliphatic or aromatic solventor a mixture thereof. Typical examples are, for example, solvents of theSolvesso series, toluene or xylene, or 2-ethylhexanol, or2-propylheptanol, or else butyldiglycol, butylglycol,methoxypropoxypropanol, butoxydipropanol or straight-chain and branchedsaturated hydrocarbons, such as paraffins or naphthenes. However, thequaternization can also be performed in the absence of a solvent.

The quaternization can be conducted in the presence of a protic solvent,optionally also in combination with an aliphatic or aromatic solvent.Suitable protic solvents especially have a dielectric constant (at 20°C.) of greater than 7. The protic solvent may comprise one or more OHgroups and may also be water. Suitable solvents may also be alcohols,glycols and glycol ethers. More particularly, suitable protic solventsmay be those mentioned in WO 2010132259. Especially suitable solventsare methanol, ethanol, n-propanol, isopropanol, all the isomers ofbutanol, all the isomers of pentanol, all the isomers of hexanol,2-ethylhexanol, 2-propylheptanol, and also mixtures of various alcohols.The presence of a protic solvent can have a positive effect on theconversion and reaction rate of the quaternization.

b) Workup of the Reaction Mixture

The reaction end product thus formed can theoretically be purifiedfurther, or the solvent can be removed. Optionally, excess reagent, forexample excess epoxide, can be removed. This can be accomplished, forexample, by introducing nitrogen at standard pressure or under reducedpressure. In order to improve the further processability of theproducts, however, it is also possible to add solvents after thereaction, for example solvents of the Solvesso series, 2-ethylhexanol,or essentially aliphatic solvents. Usually, however, this is notabsolutely necessary, and so the reaction product is usable withoutfurther purification as an additive, optionally after blending withfurther additive components (see below).

In a preferred embodiment of the present invention, the quaternizedammonium compounds have a weight loss in a thermogravimetric analysis(TGA) at 350° C. of less than 50% by weight, for example less than 40%,less than 35%, less than 30%, less than 20% or less than 15%, forexample down to 0% to 5% of weight loss.

For this purpose, a thermogravimetric analysis (TGA) is conducted inaccordance with standard ISO-4154. Specifically, in the test, a run from50° to 900° C. is conducted at a rate of temperature rise of 20° C. perminute under a nitrogen atmosphere at a flow rate of 60 mL per minute.

Use

The use of the invention relates to the inhibition of corrosion of iron,steel and/or nonferrous metal surfaces.

Among the nonferrous metals, preference is given to copper and alloysthereof.

Particular preference is given to inhibiting the corrosion of steelsurfaces.

The reaction products described are added to fuels having theabove-specified content of alkali metals and/or alkaline earth metalsand/or zinc for the effect as a corrosion inhibitor generally in amountsof 1 to 60 and preferably 4 to 50 ppm by weight, and more preferablyfrom 10 to 40 ppm by weight.

In order to show an effect against deposits on valves and/or antistaticaction, the reaction products described are added to the fuels generallyin amounts of 10 to 120 and preferably 20 to 100 ppm by weight, and morepreferably of 30 to 80 ppm by weight.

Frequently, the reaction products described are used in the form of fueladditive mixtures, together with customary additives:

In the case of diesel fuels, these are primarily customary detergentadditives, carrier oils, cold flow improvers, lubricity improvers,corrosion inhibitors other than the reaction products described,demulsifiers, dehazers, antifoams, cetane number improvers, combustionimprovers, antioxidants or stabilizers, antistats, metallocenes, metaldeactivators, dyes and/or solvents.

In the case of gasoline fuels, these are in particular lubricityimprovers (friction modifiers), corrosion inhibitors other than thereaction products described, demulsifiers, dehazers, antifoams,combustion improvers, antioxidants or stabilizers, antistats,metallocenes, metal deactivators, dyes and/or solvents.

Typical examples of suitable coadditives are listed in the followingsection:

B1) Detergent Additives

The customary detergent additives are preferably amphiphilic substanceswhich possess at least one hydrophobic hydrocarbon radical with anumber-average molecular weight (Ma) of 85 to 20 000 and at least onepolar moiety selected from:

-   (Da) mono- or polyamino groups having up to 6 nitrogen atoms, at    least one nitrogen atom having basic properties;-   (Db) nitro groups, optionally in combination with hydroxyl groups;-   (Dc) hydroxyl groups in combination with mono- or polyamino groups,    at least one nitrogen atom having basic properties;-   (Dd) carboxyl groups or the alkali metal or alkaline earth metal    salts thereof;-   (De) sulfonic acid groups or the alkali metal or alkaline earth    metal salts thereof;-   (Df) polyoxy-C₂- to C₄-alkylene moieties terminated by hydroxyl    groups, mono- or polyamino groups, at least one nitrogen atom having    basic properties, or by carbamate groups;-   (Dg) carboxylic ester groups;-   (Dh) moieties derived from succinic anhydride and having hydroxyl    and/or amino and/or amido and/or imido groups; and/or-   (Di) moieties obtained by Mannich reaction of substituted phenols    with aldehydes and mono- or polyamines.

The hydrophobic hydrocarbon radical in the above detergent additives,which ensures the adequate solubility in the fuel, has a number-averagemolecular weight (M_(n)) of 85 to 20 000, preferably of 113 to 10 000,more preferably of 300 to 5000, even more preferably of 300 to 3000,even more especially preferably of 500 to 2500 and especially of 700 to2500, in particular of 800 to 1500. Typical hydrophobic hydrocarbonradicals include especially polypropenyl, polybutenyl and polyisobutenylradicals with a number-average molecular weight M_(n) of preferably ineach case 300 to 5000, more preferably 300 to 3000, even more preferably500 to 2500, even more especially preferably 700 to 2500 and especially800 to 1500.

Examples of the above groups of detergent additives include thefollowing:

Additives comprising mono- or polyamino groups (Da) are preferablypolyalkenemono- or polyalkenepolyamines based on polypropene or onhigh-reactivity (i.e. having predominantly terminal double bonds) orconventional (i.e. having predominantly internal double bonds)polybutene or polyisobutene with M_(n)=300 to 5000, more preferably 500to 2500 and especially 700 to 2500. Such additives based onhigh-reactivity potyisobutene, which can be prepared from thepolyisobutene which may comprise up to 20% by weight of n-butene unitsby hydroformylation and reductive amination with ammonia, monoamines orpolyamines such as dimethylaminopropylamine, ethylenediamine,diethylenetriamine, triethylenetetramine or tetraethylenepentamine, areknown especially from EP-A 244 616. When polybutene or polyisobutenehaving predominantly internal double bonds (usually in the β and γpositions) are used as starting materials in the preparation of theadditives, a possible preparative route is by chlorination andsubsequent amination or by oxidation of the double bond with air orozone to give the carbonyl or carboxyl compound and subsequent aminationunder reductive (hydrogenating) conditions. The amines used here for theamination may be, for example, ammonia, monoamines or the abovementionedpolyamines. Corresponding additives based on polypropene are describedmore particularly in WO-A 94/24231.

Further particular additives comprising monoanmino groups (Da) are thehydrogenation products of the reaction products of polyisobutenes havingan average degree of polymerization P=5 to 100 with nitrogen oxides ormixtures of nitrogen oxides and oxygen, as described more particularlyin WO-A 97/03946.

Further particular additives comprising monoamino groups (Da) are thecompounds obtainable from polyisobutene epoxides by reaction with aminesand subsequent dehydration and reduction of the amino alcohols, asdescribed more particularly in DE-A 196 20 262.

Additives comprising nitro groups (Db), optionally in combination withhydroxyl groups, are preferably reaction products of polyisobuteneshaving an average degree of polymerization P=5 to 100 or 10 to 100 withnitrogen oxides or mixtures of nitrogen oxides and oxygen, as describedmore particularly in WO-A 96/03367 and in WO-A 96/03479. These reactionproducts are generally mixtures of pure nitropolyisobutenes (e.g.α,β-dinitropolyisobutene) and mixed hydroxynitropolyisobutenes (e.g.α-nitro-β-hydroxypolyisobutene).

Additives comprising hydroxyl groups in combination with mono- orpolyamino groups (Dc) are especially reaction products of polyisobuteneepoxides obtainable from polyisobutene having preferably predominantlyterminal double bonds and M_(n)=300 to 5000, with ammonia or mono- orpolyamines, as described more particularly in EP-A 476 485.

Additives comprising carboxyl groups or their alkali metal or alkalineearth metal salts (Dd) are preferably copolymers of C₂- to C₄₀-olefinswith maleic anhydride which have a total molar mass of 500 to 20 000 andwherein some or all of the carboxyl groups have been converted to thealkali metal or alkaline earth metal salts and any remainder of thecarboxyl groups has been reacted with alcohols or amines. Such additivesare disclosed more particularly by EP-A 307 815. Such additives servemainly to prevent valve seat wear and can, as described in WO-A87/01126, advantageously be used in combination with customary fueldetergents such as poly(iso)buteneamines or polyetheramines.

Additives comprising sulfonic acid groups or their alkali metal oralkaline earth metal salts (De) are preferably alkali metal or alkalineearth metal salts of an alkyl sulfosuccinate, as described moreparticularly in EP-A 639 632. Such additives serve mainly to preventvalve seat wear and can be used advantageously in combination withcustomary fuel detergents such as poly(iso)buleneamines orpolyetheramines.

Additives comprising polyoxy-C₂-C₄-alkylene moieties (Df) are preferablypolyethers or polyetheramines which are obtainable by reaction of C₂- toC₆₀-alkanols, C₆- to C₃₀-alkanediols, mono- or di-C₂- toC₃₀-alkylamines, C₁- to C₃₀-alkylcyclohexanols or C₁- toC₃₀-alkylphenols with 1 to 30 mol of ethylene oxide and/or propyleneoxide and/or butylene oxide per hydroxyl group or amino group and, inthe case of the polyetheramines, by subsequent reductive amination withammonia, monoamines or polyamines. Such products are described moreparticularly in EP-A 310 875, EP-A 356 725, EP-A 700 985 and U.S. Pat.No. 4,877,416. In the case of polyethers, such products also havecarrier oil properties. Typical examples thereof are tridecanolbutoxylates or isotridecanol butoxylates, isononylphenol butoxylates andalso polyisobutenol butoxylates and propoxylates, and also thecorresponding reaction products with ammonia.

Additives comprising carboxylic ester groups (Dg) are preferably estersof mono-, di- or tricarboxylic acids with long-chain alkanois orpolyols, especially those having a minimum viscosity of 2 mm²/s at 100°C., as described more particularly in DE-A 38 38 918. The mono-, di- ortricarboxylic acids used may be aliphatic or aromatic acids, andparticularly suitable ester alcohols or ester polyols are long-chainrepresentatives having, for example, 6 to 24 carbon atoms. Typicalrepresentatives of the esters are adipates, phthalates, isophthalates,terephthalates and trimellitates of isooctanol, of isononanol, ofisodecanol and of isotridecanol. Such products also satisfy carrier oilproperties.

Additives comprising moieties derived from succinic anhydride and havinghydroxyl and/or amino and/or amido and/or especially imido groups (Dh)are preferably corresponding derivatives of alkyl- oralkenyl-substituted succinic anhydride and especially the correspondingderivatives of polyisobutenylsuccinic anhydride which are obtainable byreacting conventional or high-reactivity polyisobutene havingM_(n)=preferably 300 to 5000, more preferably 300 to 3000, even morepreferably 500 to 2500, even more especially preferably 700 to 2500 andespecially 800 to 1500, with maleic anhydride by a thermal route in anene reaction or via the chlorinated polyisobutene. The moieties havinghydroxyl and/or amino and/or amido and/or imido groups are, for example,carboxylic acid groups, acid amides of monoamines, acid amides of di- orpolyamines which, in addition to the amide function, also have freeamine groups, succinic acid derivatives having an acid and an amidefunction, carboximides with monoamines, carboximides with di- orpolyamines which, in addition to the imide function, also have freeamine groups, or diimides which are formed by the reaction of di- orpolyamines with two succinic acid derivatives. Such fuel additives arecommon knowledge and are described, for example, in documents (1) and(2). They are preferably the reaction products of alkyl- oralkenyl-substituted succinic acids or derivatives thereof with aminesand more preferably the reaction products of polyisobutenyl-substitutedsuccinic acids or derivatives thereof with amines. Of particularinterest in this context are reaction products with aliphatic polyamines(polyalkyleneimines) such as especially ethylenediamine,diethylenetriamine, triethylenetetramine, tetraethylenepentamine,pentaethylenehexamine and hexaethyleneheptamine, which have an imidestructure.

Additives comprising moieties (Di) obtained by Mannich reaction ofsubstituted phenols with aldehydes and mono- or polyamines arepreferably reaction products of polyisobutene-substituted phenols withformaldehyde and mono- or polyamines such as ethylenediamine,diethylenetriamine, triethylenetetramine, tetraethylenepentamine ordimethylaminopropylamine. The polyisobutenyl-substituted phenols mayoriginate from conventional or high-reactivity polyisobutene havingM_(n)=300 to 5000. Such “polyisobutene Mannich bases” are described moreparticularly in EP-A 831 141.

One or more of the detergent additives mentioned can be added to thefuel in such an amount that the dosage rate of these detergent additivesis preferably 25 to 2500 ppm by weight, especially 75 to 1500 ppm byweight, in particular 150 to 1000 ppm by weight.

B2) Carrier Oils

Carrier oils additionally used may be of mineral or synthetic nature.Suitable mineral carrier oils are fractions obtained in crude oilprocessing, such as brightstock or base oils having viscosities, forexample, from the SN 500-2000 class; but also aromatic hydrocarbons,paraffinic hydrocarbons and alkoxyalkanols. Likewise useful is afraction which is obtained in the refining of mineral oil and is knownas “hydrocrack oil” (vacuum distillate cut having a boiling range offrom about 360 to 500° C., obtainable from natural mineral oil which hasbeen catalytically hydrogenated under high pressure and isomerized andalso deparaffinized). Likewise suitable are mixtures of theabovementioned mineral carrier oils.

Examples of suitable synthetic carrier oils are polyolefins(polyalphaolefins or polyinternalolefins), (poly)esters,(poly)alkoxylates, polyethers, aliphatic polyether-amines,alkylphenol-started polyethers, alkylphenol-started polyetheramines andcarboxylic esters of long-chain alkanols.

Examples of suitable polyolefins are olefin polymers having M_(n)=400 to1800, in particular based on polybutene or polyisobutene (hydrogenatedor unhydrogenated).

Examples of suitable polyethers or polyetheramines are preferablycompounds comprising polyoxy-C₂- to C₄-alkylene moieties obtainable byreacting C₂- to C₆₀-alkanols, C₆- to C₃₀-alkanediols, mono- or di-C₂- toC₃₀-alkylamines, C₁- to C₃₀-alkylcyclohexanols or C- to C₃₀-alkylphenolswith 1 to 30 mol of ethylene oxide and/or propylene oxide and/orbutylene oxide per hydroxyl group or amino group, and, in the case ofthe polyetheramines, by subsequent reductive amination with ammonia,monoamines or polyamines. Such products are described more particularlyin EP-A 310 875, EP-A 356 725, EP-A 700 985 and U.S. Pat. No. 4,877,416.For example, the polyetheramines used may be poly-C₂- to C₆-alkyleneoxide amines or functional derivatives thereof. Typical examples thereofare tridecanol butoxylates or isotridecanol butoxylates, isononylphenolbutoxylates and also polyisobutenol butoxylates and propoxylates, andalso the corresponding reaction products with ammonia.

Examples of carboxylic esters of long-chain alkanols are moreparticularly esters of mono-, di- or tricarboxylic acids with long-chainalkanols or polyols, as described more particularly in DE-A 38 38 918.The mono-, di- or tricarboxylic acids used may be aliphatic or aromaticacids; particularly suitable ester alcohols or ester polyols arelong-chain representatives having, for example, 6 to 24 carbon atoms.Typical representatives of the esters are adipates, phthalates,isophthalates, terephthalates and trimellitates of isooctanol,isononanol, isodecanol and isotridecanol, for example di(n- orisotridecyl) phthalate.

Further suitable carrier oil systems are described, for example, in DE-A38 26 608, DE-A 41 42 241, DE-A 43 09 074, EP-A 452 328 and EP-A 548617.

Examples of particularly suitable synthetic carrier oils arealcohol-started polyethers having about 5 to 35, preferably about 5 to30, more preferably 10 to 30 and especially 15 to 30 C₃- to C₆-alkyleneoxide units, for example propylene oxide, n-butylene oxide andisobutylene oxide units, or mixtures thereof, per alcohol molecule.Nonlimiting examples of suitable starter alcohols are long-chainalkanols or phenols substituted by long-chain alkyl in which thelong-chain alkyl radical is especially a straight-chain or branched C₆-to C₁₈-alkyl radical. Particular examples include tridecanol andnonylphenol. Particularly preferred alcohol-started polyethers are thereaction products (polyetherification products) of monohydric aliphaticC₆- to C₁₈-alcohols with C₃- to C₆-alkylene oxides. Examples ofmonohydric aliphatic C₆-C₁₈-alcohols are hexanol, heptanol, octanol,2-ethylhexanol, nonyl alcohol, decanol, 3-propylheptanol, undecanol,dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol,octadecanol and the constitutional and positional isomers thereof. Thealcohols can be used either in the form of the pure isomers or in theform of technical grade mixtures. A particularly preferred alcohol istridecanol. Examples of C₃- to C₆-alkylene oxides are propylene oxide,such as 1,2-propylene oxide, butylene oxide, such as 1,2-butylene oxide,2,3-butylene oxide, isobutylene oxide or tetrahydrofuran, pentyleneoxide and hexylene oxide. Particular preference among these is given toC₃- to C₄-alkylene oxides, i.e. propylene oxide such as 1,2-propyleneoxide and butylene oxide such as 1,2-butylene oxide, 2,3-butylene oxideand isobutylene oxide. Especially butylene oxide is used.

Further suitable synthetic carrier oils are alkoxylated alkylphenols, asdescribed in DE-A 10 102 913.

Particular carrier oils are synthetic carrier oils, particularpreference being given to the above-described alcohol-startedpolyethers.

The carrier oil or the mixture of different carrier oils is added to thefuel in an amount of preferably 1 to 1000 ppm by weight, more preferablyof 10 to 500 ppm by weight and especially of 20 to 100 ppm by weight.

B3) Cold Flow Improvers

Suitable cold flow improvers are in principle all organic compoundswhich are capable of improving the flow performance of middle distillatefuels or diesel fuels under cold conditions. For the intended purpose,they must have sufficient oil solubility. More particularly, useful coldflow improvers for this purpose are the cold flow improvers (middledistillate flow improvers, MDFIs) typically used in the case of middledistillates of fossil origin, i.e. in the case of customary mineraldiesel fuels. However, it is also possible to use organic compoundswhich partly or predominantly have the properties of a wax antisettlingadditive (WASA) when used in customary diesel fuels. They can also actpartly or predominantly as nucleators. It is also possible to usemixtures of organic compounds effective as MDFIs and/or effective asWASAs and/or effective as nucleators.

The cold flow improver is typically selected from

(K1) copolymers of a C₂- to C₄₀-olefin with at least one furtherethylenically unsaturated monomer;(K2) comb polymer;(K3) polyoxyalkylenes;(K4) polar nitrogen compounds;(K5) sulfocarboxylic acids or sulfonic acids or derivatives thereof; and(K6) poly(meth)acrylic esters.

It is possible to use either mixtures of different representatives fromone of the particular classes (K1) to (K6) or mixtures ofrepresentatives from different classes (K1) to (K6).

Suitable C₂- to C₄₀-olefin monomers for the copolymers of class (K1)are, for example, those having 2 to 20 and especially 2 to 10 carbonatoms, and 1 to 3 and preferably 1 or 2 carbon-carbon double bonds,especially having one carbon-carbon double bond. In the latter case, thecarbon-carbon double bond may be arranged either terminally (α-olefins)or internally. However, preference is given to α-olefins, particularpreference to α-olefins having 2 to 8 carbon atoms, for example propene,1-butene, 1-pentene, 1-hexene and in particular ethylene.

In the copolymers of class (K1), the at least one further ethylenicallyunsaturated monomer is preferably selected from alkenyl carboxylates,(meth)acrylic esters and further olefins.

When further olefins are also copolymerized, they are preferably higherin molecular weight than the abovementioned C₂- to C₄₀-olefin basemonomers. When, for example, the olefin base monomer used is ethylene orpropene, suitable further olefins are especially C₁₀- to C₄₀-α-olefins.Further olefins are in most cases only additionally copolymerized whenmonomers with carboxylic ester functions are also used.

Suitable (meth)acrylic esters are, for example, esters of (meth)acrylicacid with C₁- to Ca-alkanols, especially C₁- to C₁₀-alkanols, inparticular with methanol, ethanol, propanol, isopropanol, n-butanol,sec-butanol, isobutanol, tert-butanol, pentanol, hexanol, heptanol,octanol, 2-ethylhexanol, nonanol and decanol, and structural isomersthereof.

Suitable alkenyl carboxylates are, for example, C₂- to C₁₄-alkenylesters, for example the vinyl and propenyl esters, of carboxylic acidshaving 2 to 21 carbon atoms, whose hydrocarbyl radical may be linear orbranched. Among these, preference is given to the vinyl esters. Amongthe carboxylic acids with a branched hydrocarbyl radical, preference isgiven to those whose branch is in the α position to the carboxyl group,and the α-carbon atom is more preferably tertiary, i.e. the carboxylicacid is what is called a neocarboxylic acid. However, the hydrocarbylradical of the carboxylic acid is preferably linear.

Examples of suitable alkenyl carboxylates are vinyl acetate, vinylpropionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl neopentanoate,vinyl hexanoate, vinyl neononanoate, vinyl neodecanoate and thecorresponding propenyl esters, preference being given to the vinylesters. A particularly preferred alkenyl carboxylate is vinyl acetate;typical copolymers of group (K1) resulting therefrom are ethylene-vinylacetate copolymers (“EVAs”), which are some of the most frequently used.

Ethylene-vinyl acetate copolymers usable particularly advantageously andthe preparation thereof are described in WO 99/29748.

Suitable copolymers of class (K1) are also those which comprise two ormore different alkenyl carboxylates in copolymerized form, which differin the alkenyl function and/or in the carboxylic acid group. Likewisesuitable are copolymers which, as well as the alkenyl carboxylate(s),comprise at least one olefin and/or at least one (meth)acrylic ester incopolymerized form.

Terpolymers of a C₂- to C₄₀-α-olefin, a C₁- to C₂₀-alkyl ester of anethylenically unsaturated monocarboxylic acid having 3 to 15 carbonatoms and a C₂- to C₁₄-alkenyl ester of a saturated monocarboxylic acidhaving 2 to 21 carbon atoms are also suitable as copolymers of class(K1). Terpolymers of this kind are described in WO 2005/054314. Atypical terpolymer of this kind is formed from ethylene, 2-ethylhexylacrylate and vinyl acetate.

The at least one or the further ethylenically unsaturated monomer(s) arecopolymerized in the copolymers of class (K1) in an amount of preferably1 to 50% by weight, especially 10 to 45% by weight and in particular 20to 40% by weight, based on the overall copolymer. The main proportion interms of weight of the monomer units in the copolymers of class (K1)therefore originates generally from the C₂- to C₄₀ base olefins.

The copolymers of class (K1) preferably have a number-average molecularweight M_(n) of 1000 to 20 000, more preferably of 1000 to 10 000 andespecially of 1000 to 8000.

Typical comb polymers of component (K2) are, for example, obtainable bythe copolymerization of maleic anhydride or fumaric acid with anotherethylenically unsaturated monomer, for example with an α-olefin or anunsaturated ester, such as vinyl acetate, and subsequent esterificationof the anhydride or acid function with an alcohol having at least 10carbon atoms. Further suitable comb polymers are copolymers of α-olefinsand esterified comonomers, for example esterified copolymers of styreneand maleic anhydride or esterified copolymers of styrene and fumaricacid. Suitable comb polymers may also be polyfumarates or polymaleates.Homo- and copolymers of vinyl ethers are also suitable comb polymers.Comb polymers suitable as components of class (K2) are, for example,also those described in WO 2004/035715 and in “Comb-Like Polymers,Structure and Properties”, N. A. Platé and V. P. Shibaev, J. Poly. Sci.Macromolecular Revs. 8, pages 117 to 253 (1974). Mixtures of combpolymers are also suitable.

Polyoxyalkylenes suitable as components of class (K3) are, for example,polyoxyalkylene esters, polyoxyalkylene ethers, mixed polyoxyalkyleneester/ethers and mixtures thereof. These polyoxyalkylene compoundspreferably comprise at least one linear alkyl group, preferably at leasttwo linear alkyl groups, each having 10 to 30 carbon atoms and apolyoxyalkylene group having a number-average molecular weight of up to5000. Such polyoxyalkylene compounds are described, for example, in EP A061 895 and also in U.S. Pat. No. 4,491,455. Particular polyoxyalkylenecompounds are based on polyethylene glycols and polypropylene glycolshaving a number-average molecular weight of 100 to 5000. Additionallysuitable are polyoxyalkylene mono- and diesters of fatty acids having 10to 30 carbon atoms, such as stearic acid or behenic acid.

Polar nitrogen compounds suitable as components of class (K4) may beeither ionic or nonionic and preferably have at least one substituent,especially at least two substituents, in the form of a tertiary nitrogenatom of the general formula >NR⁷ in which R⁷ is a Cr to C₄₀-hydrocarbylradical. The nitrogen substituents may also be quaternized, i.e. be incationic form. An example of such nitrogen compounds is that of ammoniumsalts and/or amides which are obtainable by the reaction of at least oneamine substituted by at least one hydrocarbyl radical with a carboxylicacid having 1 to 4 carboxyl groups or with a suitable derivativethereof. The amines preferably comprise at least one linear C₈- toC₄₀-alkyl radical. Primary amines suitable for preparing the polarnitrogen compounds mentioned are, for example, octylamine, nonylamine,decylamine, undecylamine, dodecylamine, tetradecylamine and the higherlinear homologs; secondary amines suitable for this purpose are, forexample, dioctadecylamine and methylbehenylamine. Also suitable for thispurpose are amine mixtures, especially amine mixtures obtainable on theindustrial scale, such as fatty amines or hydrogenated tallamines, asdescribed, for example, in Ullmann's Encyclopedia of IndustrialChemistry, 6th Edition, “Amines, aliphatic” chapter. Acids suitable forthe reaction are, for example, cyclohexane-1,2-dicarboxylic acid,cyclohexene-1,2-dicarboxylic acid, cyclopentane-1,2-dicarboxylic acid,naphthalenedicarboxylic acid, phthalic acid, isophthalic acid,terephthalic acid, and succinic acids substituted by long-chainhydrocarbyl radicals.

More particularly, the component of class (K4) is an oil-solublereaction product of poly(C₂- to C₂₀-carboxylic acids) having at leastone tertiary amino group with primary or secondary amines. The poly(C₂-to -C₂₀-carboxylic acids) which have at least one tertiary amino groupand form the basis of this reaction product comprise preferably at least3 carboxyl groups, especially 3 to 12 and in particular 3 to 5 carboxylgroups. The carboxylic acid units in the polycarboxylic acids havepreferably 2 to 10 carbon atoms, and are especially acetic acid units.The carboxylic acid units are suitably bonded to the polycarboxylicacids, usually via one or more carbon and/or nitrogen atoms. They arepreferably attached to tertiary nitrogen atoms which, in the case of aplurality of nitrogen atoms, are bonded via hydrocarbon chains.

The component of class (K4) is preferably an oil-soluble reactionproduct based on poly(C₂- to C₂₀-carboxylic acids) which have at leastone tertiary amino group and are of the general formula IIa or IIb

in which the variable A is a straight-chain or branched C₂- toC₆-alkylene group or the moiety of the formula III

and the variable B is a C₁- to C₁₉-alkylene group. The compounds of thegeneral formulae IIa and IIb especially have the properties of a WASA.

Moreover, the preferred oil-soluble reaction product of component (K4),especially that of the general formula IIa or IIb, is an amide, anamide-ammonium salt or an ammonium salt in which no, one or morecarboxylic acid groups have been converted to amide groups.

Straight-chain or branched C₂- to C₆-alkylene groups of the variable Aare, for example, 1,1-ethylene, 1,2-propylene, 1,3-propylene,1,2-butylene, 1,3-butylene, 1,4-butylene, 2-methyl-1,3-propylene,1,5-pentylene, 2-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene,1,6-hexylene (hexamethylene) and especially 1,2-ethylene. The variable Acomprises preferably 2 to 4 and especially 2 or 3 carbon atoms.

C₁- to C₁₉-alkylene groups of the variable B are, for example,1,2-ethylene, 1,3-propylene, 1,4-butylene, hexamethylene, octamethylene,decamethylene, dodecamethylene, tetradecamethylene, hexadecamethylene,octadecamethylene, nonadecamethylene and especially methylene. Thevariable B comprises preferably 1 to 10 and especially 1 to 4 carbonatoms.

The primary and secondary amines as a reaction partner for thepolycarboxylic acids to form component (K4) are typically monoamines,especially aliphatic monoamines. These primary and secondary amines maybe selected from a multitude of amines which bear hydrocarbyl radicalswhich may optionally be bonded to one another.

These parent amines of the oil-soluble reaction products of component(K4) are usually secondary amines and have the general formula HN(R⁸)₂in which the two variables R⁸ are each independently straight-chain orbranched C₁₀- to C₃₀-alkyl radicals, especially C₁₄- to C₂₄-alkylradicals. These relatively long-chain alkyl radicals are preferablystraight-chain or only slightly branched. In general, the secondaryamines mentioned, with regard to their relatively long-chain alkylradicals, derive from naturally occurring fatty acids and fromderivatives thereof. The two R⁸ radicals are preferably identical.

The secondary amines mentioned may be bonded to the polycarboxylic acidsby means of amide structures or in the form of the ammonium salts; it isalso possible for only a portion to be present as amide structures andanother portion as ammonium salts. Preferably only few, if any, freeacid groups are present. The oil-soluble reaction products of component(K4) are preferably present completely in the form of the amidestructures.

Typical examples of such components (K4) are reaction products ofnitrilotriacetic acid, of ethylenediaminetetraacetic acid or ofpropylene-1,2-diaminetetraacetic acid with in each case 0.5 to 1.5 molper carboxyl group, especially 0.8 to 1.2 mol per carboxyl group, ofdioleylamine, dipalmitamine, dicocoamine, distearylamine, dibehenylamineor especially ditalamine. A particularly preferred component (K4) is thereaction product of 1 mol of ethylenediaminetetraacetic acid and 4 molof hydrogenated ditallamine.

Further typical examples of component (K4) include theN,N-dialkylammonium salts of 2-N′,N′-dialkylamidobenzoates, for examplethe reaction product of 1 mol of phthalic anhydride and 2 mol ofditallamine, the latter being hydrogenated or unhydrogenated, and thereaction product of 1 mol of an alkenylspirobislactone with 2 mol of adialkylamine, for example ditallamine and/or tallamine, the latter twobeing hydrogenated or unhydrogenated.

Further typical structure types for the component of class (K4) arecyclic compounds with tertiary amino groups or condensates of long-chainprimary or secondary amines with carboxylic acid-containing polymers, asdescribed in WO 93/18115.

Sulfocarboxylic acids, sulfonic acids or derivatives thereof which aresuitable as cold flow improvers of the component of class (K5) are, forexample, the oil-soluble carboxamides and carboxytic esters ofortho-sulfobenzoic acid, in which the sulfonic acid function is presentas a sulfonate with alkyl-substituted ammonium cations, as described inEP-A 261 957.

Poly(meth)acrylic esters suitable as cold flow improvers of thecomponent of class (K6) are either homo- or copolymers of acrylic andmethacrylic esters. Preference is given to copolymers of at least twodifferent (meth)acrylic esters which differ with regard to theesterified alcohol. The copolymer optionally comprises another differentolefinically unsaturated monomer in copolymerized form. Theweight-average molecular weight of the polymer is preferably 50 000 to500 000. A particularly preferred polymer is a copolymer of methacrylicacid and methacrylic esters of saturated C₁₄- and C₁₅-alcohols, the acidgroups having been neutralized with hydrogenated tallamine. Suitablepoly(meth)acrylic esters are described, for example, in WO 00/44857.

The cold flow improver or the mixture of different cold flow improversis added to the middle distillate fuel or diesel fuel in a total amountof preferably 10 to 5000 ppm by weight, more preferably of 20 to 2000ppm by weight, even more preferably of 50 to 1000 ppm by weight andespecially of 100 to 700 ppm by weight, for example of 200 to 500 ppm byweight.

B4) Lubricity Improvers

Suitable lubricity improvers or friction modifiers are based typicallyon fatty acids or fatty acid esters. Typical examples are tall oil fattyacid, as described, for example, in WO 98/004656, and glycerylmonooleate. The reaction products, described in U.S. Pat. No. 6,743,266B2, of natural or synthetic oils, for example triglycerides, andalkanolamines are also suitable as such lubricity improvers.

B5) Corrosion Inhibitors Other than the Reaction Product Described

Suitable corrosion inhibitors are, for example, succinic esters, inparticular with polyols, fatty acid derivatives, for example oleicesters, oligomerized fatty acids, substituted ethanolamines, andproducts sold under the trade name RC 4801 (Rhein Chemie Mannheim,Germany), Irgacor L12 (BASF SE) or HiTEC 536 (Ethyl Corporation).

B6) Demulsifiers

Suitable demulsifiers are, for example, the alkali metal or alkalineearth metal salts of alkyl-substituted phenol- and naphthalenesulfonatesand the alkali metal or alkaline earth metal salts of fatty acids, andalso neutral compounds such as alcohol alkoxylates, e.g. alcoholethoxylates, phenol alkoxylates, e.g. tert-butylphenol ethoxylate ortert-pentylphenol ethoxylate, fatty acids, alkylphenols, condensationproducts of ethylene oxide (EO) and propylene oxide (PO), for exampleincluding in the form of EO/PO block copolymers, polyethyleneimines orelse polysiloxanes.

B7) Dehazers

Suitable dehazers are, for example, alkoxylated phenol-formaldehydecondensates, for example the products available under the trade namesNALCO 7D07 (Nalco) and TOLAD 2683 (Petrolite).

B8) Antifoams

Suitable antifoams are, for example, polyether-modified polysiloxanes,for example the products available under the trade names TEGOPREN 5851(Goldschmldt), Q 25907 (Dow Corning) and RHODOSIL (Rhone Poulenc).

B9) Cetane Number Improvers

Suitable cetane number improvers are, for example, aliphatic nitratessuch as 2-ethyihexyl nitrate and cyclohexyl nitrate and peroxides suchas di-tert-butyl peroxide.

B10) Antioxidants

Suitable antioxidants are, for example substituted phenols, such as2,6-di-tert-butylphenol and 6-di-tert-butyl-3-methylphenol, and alsophenylenediamines such as N,N′-di-sec-butyl-p-phenylenediamine.

B11) Metal Deactivators

Suitable metal deactivators are, for example, salicylic acid derivativessuch as N,N′-disalicylidene-1,2-propanediamine.

B12) Solvents

Suitable solvents are, for example, nonpolar organic solvents such asaromatic and aliphatic hydrocarbons, for example toluene, xylenes, whitespirit and products sold under the trade names SHELLSOL (RoyalDutch/Shell Group) and EXXSOL (ExxonMobil), and also polar organicsolvents, for example, alcohols such as 2-ethylhexanol, decanol andisotridecanol. Such solvents are usually added to the diesel fueltogether with the aforementioned additives and coadditives, which theyare intended to dissolve or dilute for better handling.

C) Fuels

The inventive use relates in principle to any fuel, preferably dieseland gasoline fuels.

Middle distillate fuels such as diesel fuels or heating oils arepreferably mineral oil raffinates which typically have a boiling rangefrom 100 to 400° C. These are usually distillates having a 95% point upto 360° C. or even higher. These may also be what is called “ultra lowsulfur diesel” or “city diesel”, characterized by a 95% point of, forexample, not more than 345° C. and a sulfur content of not more than0.005% by weight or by a 95% point of, for example, 285° C. and a sulfurcontent of not more than 0.001% by weight. In addition to the mineralmiddle distillate fuels or diesel fuels obtainable by refining, thoseobtainable by coal gasification or gas liquefaction [“gas to liquid”(GTL) fuels] or by biomass liquefaction [“biomass to liquid” (BTL)fuels] are also suitable. Also suitable are mixtures of theaforementioned middle distillate fuels or diesel fuels with renewablefuels, such as biodiesel or bioethanol.

The qualities of the heating oils and diesel fuels are laid down indetail, for example, in DIN 51603 and EN 590 (cf. also Ullmann'sEncyclopedia of industrial Chemistry, 5th edition, Volume A12, p. 617ff.).

The inventive use in middle distillate fuels of fossil, vegetable oranimal origin, which are essentially hydrocarbon mixtures, also relatesto mixtures of such middle distillates with biofuel oils (biodiesel).Such mixtures are encompassed by the term “middle distillate fuel”. Theyare commercially available and usually comprise the biofuel oils inminor amounts, typically in amounts of 1 to 30% by weight, especially of3 to 10% by weight, based on the total amount of middle distillate offossil, vegetable or animal origin and biofuel oil.

Biofuel oils are generally based on fatty acid esters, preferablyessentially on alkyl esters of fatty acids which derive from vegetableand/or animal oils and/or fats. Alkyl esters are typically understood tomean lower alkyl esters, especially C₁- to C₄-alkyl esters, which areobtainable by transesterifying the glycerides which occur in vegetableand/or animal oils and/or fats, especially triglycerides, by means oflower alcohols, for example ethanol or in particular methanol (“FAME”).Typical lower alkyl esters based on vegetable and/or animal oils and/orfats, which find use as a biofuel oil or components thereof, are, forexample, sunflower methyl ester, palm oil methyl ester (“PME”), soya oilmethyl ester (“SME”) and especially rapeseed oil methyl ester (“RME”).

The middle distillate fuels or diesel fuels are more preferably thosehaving a low sulfur content, i.e. having a sulfur content of less than0.05% by weight, preferably of less than 0.02% by weight, moreparticularly of less than 0.005% by weight and especially of less than0.001% by weight of sulfur.

Useful gasoline fuels include all commercial gasoline fuel compositions.One typical representative which shall be mentioned here is theEurosuper base fuel to EN 228, which is customary on the market. Inaddition, gasoline fuel compositions of the specification according toWO 00/47698 are also possible fields of use for the present invention.

The examples which follow are intended to illustrate the presentinvention without restricting it.

EXAMPLES GPC Analysis

Unless stated otherwise, the mass-average Mw and number-averagemolecular weight Mn of the polymers were measured by means of gelpermeation chromatography (GPC). GPC separation was effected by means oftwo PLge Mixed B columns (Agilent) in tetrahydrofuran at 35° C.Calibration was effected by means of a narrow-distribution polystyrenestandard (from PSS, Germany) having molecular weight 162-50400 Da.Hexylbenzene was used as marker for low molecular weight.

PREPARATION EXAMPLES Preparation Examples 1 to 4: Quaternization ofTertiary Fatty Amines with Propylene Oxide in the Presence of VariousHydrocarbyl-Substituted Succinic Acids

R₁ here is long-chain hydrocarbyl: R₂, R₃ and R₄ correspond to R_(a),R_(b) and R_(c) are as defined above; R₅ corresponds to R_(d) as definedabove; and R is H or is a radical produced by esterification with theepoxide, for example —CH₂CH(R₅)OH.

a) Reagents Used:

Polyisobutylenesuocinic anhydride (PIBSA, Glissopal® SA, from BASF):

Prepared from maleic anhydride and polyisobutene 1000 in a known manner.Unless stated otherwise, for the inventive preparation examples,qualities having a bismaleation level of 10% to 20% and hydrolysisnumbers in the range of 84-95 mg KOH/g were used. For preparation ofpolyisobutylenesuccinic acid, polyisobutylenesuccinic anhydride wasadmixed with the equimolar amount of water according to the hydrolysisnumber and hydrolyzed at a temperature of 80° C. For example, theconversion of polyisobutylenesuccinic anhydride (hydrolysis number 85.6mg KOH/g) after a reaction time of 4 h at 80° C. gave a reaction productwhich had an acid number of 83.9 mg KOH/g. The formation ofpolyisobutylenesuccinic acid was confirmed by IR spectroscopy (1711cm⁻¹).

In an analogous manner, tetrapropenylsuccinic anhydride (CAS 26544-38-7)and a mixed i-hexadecenyl/i-octadecenylsuccinic anhydride (CAS32072-96-1 und 28777-98-2) from Pentagon were hydrolyzed to give thecorresponding succinic acid derivatives.

Cocoyldimethylamine: (N,N-dimethyl-N—C12/14-amine, CAS 68439-70-3 and112-18-5) having a total amine number of 246 mg KOH/g.

N-Methyl-N,N-ditallowamine: Armeen® M2HT from Akzo Nobel, CAS61788-63-4, having a total amine number of 108 mg KOH/g.

The following were additionally used:

N,N-dimethylhexadecylamine (n-C₁₆H₃₃NMe₂, CAS 112-69-6, from Aldrich).

Tridecylamine (branched; isomer mixture, CAS 86089-17-0) from BASF.

N,N-Dimethyl-1,3-diaminopropane (DMAPA, CAS 109-55-7) from BASF.

2-Ethylhexanol and 2-propylheptanol from BASF.

Solvent Naphtha naphthalene depleted (ND): Solvesso™ 150 ND from ExxonMobil.

b) General Synthesis Method

A 2 l autoclave is initially charged with a solution of the tertiaryamine (1 eq. in accordance with the total amine number) and of thealkylenesuccinic acid derivative (1 eq. in accordance with the acidnumber) in the stated solvent (2-ethylhexanol, unless stated otherwise).The amount of solvent and the batch size are chosen such that the endproduct has an active content of 50% and the reactor a fill level ofabout 70%.

This is followed by purging three times with N₂, establishment of asupply pressure of approx. 2 bar of N₂ and an increase in thetemperature to 50° C. The alkylene oxide stated, propylene oxide unlessstated otherwise (2 eq.), is metered in within 1 h. This is followed bystirring at 50° C. for 15 h, cooling to 25° C., purging with N₂ andemptying of the reactor. The product is transferred into a 2 L jacketedreactor and excess alkylene oxide is removed by introducing an N₂ stream(10 I/h) under reduced pressure (70 mbar) at 50′C for 6 h. ¹H NMR(CDCl₃) confirms the quaternization (δ=3.3 ppm, singlet. R₂N(CH₃)₂ orR₃NCH₃).

c) Experiments Conducted

Following the above synthesis method, the following quaternizations wereconducted with propylene oxide:

Preparation Hydrocarbyl-substituted example Tertiary amine succinic acid1 cocoyldimethylamine polyisobutylenesuccinic acid 2 cocoyldimethylaminetetrapropenylsuccinic acid 3 cocoyldimethylamine i-hexadecenyl/i-octadecenylsuccinic acid 4 N-methyl-N,N- tetrapropenylsuccinic acidditallowamine 6 n-C₁₆H₃₃NMe₂ polyisobutylenesuccinic acid 7 n-C₁₆H₃₃NMe₂polyisobutylenesuccinic acid 8 n-C₁₆H₃₃NMe₂ polyisobutylenesuccinic acid9 n-C₁₆H₃₃NMe₂ polyisobutylenesuccinic acid 10 n-C₁₆H₃₃NMe₂polyisobutylenesuccinic acid 11 n-C₁₆H₃₃NMe₂ polyisobutylenesuccinicacid 12 n-C₁₆H₃₃NMe₂ polyisobutylenesuccinic acid 13 cocoyldimethylaminepolyisobutylenesuccinic acid 16 N,N-dimethyl- tetrapropenylsuccinic acidethanolamine*15 PO 17 PIBSA-DMAPA tetrapropenylsuccinic acid succinimide

Remarks relating to preparation examples:

-   No. 7: 2-Propylheptanol was used in place of 2-ethylhexanol as    solvent.-   No. 8: 2-Ethylhexanol/Solvent Naphtha ND 1:1 (w/w) was used in place    of 2-ethylhexanol as solvent.-   No. 9: Ethylene oxide (1.5 eq.) was used in place of propylene    oxide. 2-Propylheptanol was used in place of 2-ethylhexanol as    solvent.-   No. 10: The PIBSA used (obtained from maleic anhydride and    polyisobutene 1000) had a bismaleation level of 32% and a hydrolysis    number of 112.5 mg KOH/g.-   No. 11: 1.5 eq. of propylene oxide were used.-   No. 12: 1.1 eq. of propylene oxide were used.-   No. 13: 2-Propylheptanol was used in place of 2-ethylhexanol as    solvent. The PIBSA used (obtained from maleic anhydride and    polyisobutene 550) had a hydrolysis number of 142.5 mg KOH/g.-   No. 16: 2-Propylheptanol was used as solvent; the amine used was a    polyetheramine obtained by 15-fold propoxylation of    N,N-dimethylethanolamine (for preparation see synthesis example 1 of    WO 2013/064689 A1).-   No. 17: 2-Propylheptanol was used as solvent; the amine used was the    condensation product of polyisobutylenesuccinic acid (PIBSA) and    DMAPA, see preparation example 1 of WO 2013/000997 A1.

Preparation example 5: Quaternization of triethylamine with dodeceneoxide in the presence of tetrapropenylsuccinic acids

Reagents: dodecene oxide (CAS 2855-19-8) from Aldrich, trimethylamine(anhydrous, CAS 75-50-3) from BASF

An N₂-inertized 2 l autoclave is initially charged with a solution oftrimethylamine (47.2 g, 0.8 mol) and dodecene oxide (147.2 g, 0.8 mol)in 2-ethylhexanol (194.4 g). Subsequently, the temperature is increasedto 40° C. A solution of tetrapropenylsuccinic acid (252.8 g, 0.8 mol) in2-ethylhexanol (252.8 g) is metered in within 1.5 h. Subsequently, themixture is stirred at 40° C. for a further 15 h. Volatile constituentsare removed by introducing an N₂ stream at 40° C., then the reactor isemptied. ¹H NMR (CDCl₃) confirms the quaternization (δ=3.3 ppm, singlet,RN(CH₃)₃).

Preparation Example 14: Synthesis of iC₁₃NMe₂

Tridecylamine (140.2 g) is initially charged at room temperature andformic acid (166.7 g) is added while stirring within 15 min. Thereaction mixture is heated to 45° C. and aqueous formaldehyde solution(37%; 132.7 g) is added dropwise within 25 min, with evolution of CO₂.Subsequently, the mixture is stirred at 80° C. for 23 h. After coolingto room temperature, hydrochloric acid (32%; 121.5 g) is added whilestirring. The mixture is stirred at room temperature for 3 h and thewater is removed on a rotary evaporator under reduced pressure. Theproduct mixture is admixed with 500 ml of water and the amine isreleased with 50% sodium hydroxide solution. The mixture was extractedtwice with methyl tert-butyl ether, the combined organic phases weredried over sodium sulfate and the solvent was removed on a rotaryevaporator. The product (143.5 g) showed a total amine number of 228 mgKOH/g with 94% tertiary amine.

Preparation Example 15: Quaternization of iC₃NMe₂ with PropyleneOxide/Tetrapropenylsuccinic Acid

According to the general synthesis method, iC₁₃NMe₂ (preparation example14), tetrapropenylsuccinic acid and propylene oxide were converted in2-propylheptanol rather than 2-ethylhexanol.

Analysis Example 1 a) Determination of the Quaternization Level:

Quaternization levels are determined by ¹H NM spectroscopy. For thispurpose, the appropriate solvent is removed with a Kugelrohr still (60°C., p=10⁻³ mbar, 3 h). To determine the quaternization level, the alkylmoiety is integrated relative to the signals of the quaternized productRCH₂NMe₂CH₂CH(OH)R′. The quotients of the integrals of the signals ofthe quaternized product and of the corresponding theoretical valuesmultiplied by 100% give the quaternization level. The values for thedifferent signals are averaged. Residues of solvent (doublet at δ=3.55ppm for HOCH₂CHRR′) are taken into account.

Synthesis according to Quaternization level [%] Preparation example 1 99Preparation example 3 92 Preparation example 7 99 Preparation example 890 Preparation example 11 85

b) Thermogravimetry

For the thermogravimetry analysis, the appropriate solvent was removedwith a Kugelrohr still (60-70° C., p=10⁻³ mbar, 3 h). Thethermogravimetry was measured from 30° C. to 900° C. with a temperaturerise of 20° C./min. under a nitrogen atmosphere at a flow rate of 60mL/min. The following changes in mass (TG) were determined at 350° C.:

Synthesis according to Change in mass (TG) at 350° C. Preparationexample 1 17% Preparation example 7 34%

Use Examples

The above synthesis examples were used to produce, by mixing withpolyisobuteneamine (molar mass 1000), polypropylene glycol as carrieroil and solvent and dehazer, the additive formulations specified intable 1, and these were used in the use examples (compositions in partsby weight).

A) Calcium Compatibility Test

100 ml of motor oil (Shell Helix®, having a Ca content of 1500 ppm, Mgcontent of 1100 ppm and Zn content of 1300 ppm) were heated to 70° C. ina beaker and then 1 ml of corrosion inhibitor was added. Should thesolution still be clear, a further 1 ml of inhibitor is added. If thesolution turns cloudy, the test has been failed (for example FIG. 1,left-hand beaker).

FIG. 1 shows the oil admixed with 1 mL of product according to synthesisexample 7 (50% in 2-propylheptanol), which remains clear. In theleft-hand beaker, as a comparison, 1 mL of dimer fatty acid (dimericoleic acid; CAS: 61788-89-4, 40% in Solvent Naphtha) was used. Opacityis dearly apparent.

B) Conductivity Test

A conductivity test was conducted to DIN 51412:

Haltermann E0 base fuel: 58 ps/mFormulation 1 (comp.) (894 mg/kg of additive): 70 ps/mFormulation 2 (894 mg/kg of additive): 83 ps/m

It can be seen that the conductivity can be distinctly raised using theinventive compound from preparation example 7.

C) Steel Finger Corrosion According to ASTM D 6658: a) Gasoline Fuel

The fuel used was standard 95-octane E0 gasoline fuel from Haltermann,which was additized according to table 1 and subjected to a corrosiontest according to ASTM D 665 B.

As a comparison, in formulation 3, dimer fatty acid (dimeric oleic acid;CAS: 61788-89-4 as corrosion inhibitor dissolved in Solvent Naphtha) wasused.

Additive Dosage NACE rating Haltermann E0 base fuel E Formulation 3(comp.) 500 mg/kg A Formulation 4 500 mg/kg A Formulation 5 490 mg/kg E

The assessment was made as follows:

-   A 100% rust-free-   B++ 0.1% or less of the total surface area rusted-   B+ 0.1% to 5% of the total surface area rusted-   B 5% to 25% of the total surface area rusted-   C 25% to 50% of the total surface area rusted-   D 50% to 75% of the total surface area rusted-   E 75% to 100% of the total surface area rusted

b) Diesel Fuel

The fuel used was standard Aral DIN 590 diesel fuel, which was testedaccording to DIN D665B (in modified form) with synthetic seawater.

FIG. 2 shows, on the left, the test specimen which was tested in thefuel without further additives (rated “E” according to NACE).

FIG. 2 shows, on the right, the test specimen which was tested in thefuel with addition of 32 mg/kg of preparation example 7 (based on testsubstance) (rated “A” according to NACE).

D) PFI Engine Test DC M111E

An engine test was conducted over 60 hours according to CEC F-020-98(keep-clean mode) with MIRO 95-octane E10 fuel and RL 223 motor oil in aport fuel injector engine (M111E) and the deposits on the intake valves(internal valve deposits, IVD) were determined.

The formulations used are listed in table 2, and the results in tables 3and 4

It is apparent from table 4 that 40 mg/kg of added inventive substances(formulation 10) are capable of achieving an effect on the intake valvescomparable to that in comparative formulation 9 of a combination of 100mg/kg of detergent (Mannich PIBA) with 10 mg/kg of dimer fatty acid interms of inhibition of corrosion.

The inventive compounds are thus of comparable efficacy at lower dosage.

TABLE 1 Solvent Naphtha solvent, Synthesis example friction 2-Polyisobutene Carrier Dimer fatty acid 7 (50% 2- modifier +Propylheptanol Sum amine oil (about 40%) propylheptanol) dehazer solventtotal Formulation 1 259 156 10 409 60 894 (comp.) Formulation 2 259 15640 439 894 Formulation 3 248 195 10 47 500 (comp.) Formulation 4 248 19510 47 500 Formulation 5 248 195 47 490

TABLE 2 PIBA [mg/kg]/ Carrier Formulation Mannich Addition oil no. PIBA[mg/kg] [mg/kg] Solvent Balance 6 −/− 194 90 241 3 preparation example 37 −/− 194 90 241 3 preparation example 16 8 −/− 194 90 241 3 preparationexample 7 9 259/100 10 156 420 76 (comp) dimer fatty acid 10  259/−  40156 360 79 preparation example 7 PIBA: polyisobutene, M_(N) about 1000g/mol Mannich PIBA: Mannich product based on phenol (substituted by apolyisobutene, M_(N) about 1000 g/mol), formaldehyde and dialkylamineaccording to WO 2015 028391 having an active content of 80%.

TABLE 3 Dosage Average IVD Formulation no. (mg/kg) Fuel [mg/valve] Basevalue — Miro 95-octane E10 146 7 528 Miro 95-octane E10 136 8 528 Miro95-octane E10 122

TABLE 4 Formulation Dosage Average IVD no. [mg/kg] Fuel [mg/valve] 9(comp.) 1021 Miro 95-octane E10 2 10 894 Miro 95-octane E10 0 9 (comp.)1021 Miro 95-octane E10 2 10 894 Miro 95-octane E10 0 Base value Miro95-octane E10 86 9 (comp.) 454 Miro 95-octane E10 1 10 398 Miro95-octane E10 4 Base value Miro 95-octane E10 72 9 (comp.) 454 Miro95-octane E10 1 10 398 Miro 95-octane E10 3

1. A reaction product, comprising an optionally purified quaternizednitrogen compound, wherein, the reaction product is obtained by reactinga quaternizable nitrogen compound comprising at least one quaternizableamino group with a quaternizing agent that converts the at least onequaternizable amino group to a quaternary ammonium group; and thequaternizing agent is a hydrocarbyl epoxide in combination with a freehydrocarbyl-substituted polycarboxylic acid.
 2. (canceled) 3: A process,comprising inhibiting corrosion in a gasoline fuel, by combining thegasoline fuel with the reaction product of claim
 1. 4: A process,comprising reducing corrosion of nonferrous metals in a fuel bycombining the fuel with the reaction product of claim
 1. 5: A process,comprising increasing electrical conductivity and reducing electrostaticcharging in a fuel, by combining the fuel with the reaction product ofclaim
 1. 6: A process, comprising completely or partially preventingformation of deposits, completely or partially removing deposits, orboth, in fuel inlet and outlet valves of a gasoline engine having portfuel injectors, by operating the gasoline engine with a fuel comprisingthe reaction product of claim
 1. 7. The reaction product of claim 1,wherein the quaternizable nitrogen compound is selected from the groupconsisting of: a) at least one alkylamine comprising at least onecompound of formula (3):R_(a)R_(b)R_(c)N  (3), wherein at least one of the R_(a), R_(b) andR_(c) radicals is a straight-chain or branched, saturated or unsaturatedC₈-C₄₀-hydrocarbyl radical and the other radicals are identical ordifferent, straight-chain or branched, saturated or unsaturatedC₁-C₆-hydrocarbyl radical; b) at least one polyalkene-substituted aminecomprising at least one quaternizable amino group; c) at least onepolyether-substituted amine comprising at least one quaternizable aminogroup; and d) at least one reaction product of a hydrocarbyl-substitutedacylating agent and a compound comprising a nitrogen or oxygen atom andadditionally comprising at least one quaternizable amino group; and e)mixtures thereof. 8: The reaction product of claim 1, wherein thequaternizable nitrogen compound is an alkylamine comprising at least onecompound of formula (3):R_(a)R_(b)R_(c)N  (3), wherein the R_(a), R_(b) and R_(c) radicals areidentical or different, straight-chain or branched, saturated orunsaturated C₈-C₄₀-hydrocarbyl radicals. 9: The reaction product ofclaim 1, wherein the quaternizing agent comprises an epoxide of formula(4):

wherein: the R_(d) radicals are the same or different and represent H ora hydrocarbyl radical, the hydrocarbyl radical being an aliphatic oraromatic radical having at least 1 to 10 carbon atoms. 10: The reactionproduct of claim 1, wherein the free hydrocarbyl-substitutedpolycarboxylic acid of the quaternizing agent is ahydrocarbyl-substituted C₃-C₂₈ dicarboxylic acid. 11: The reactionproduct of claim 1, wherein a hydrocarbyl substituent of thepolycarboxylic acid is a polyalkylene radical having a polymerizationlevel of 2 to
 100. 12: The reaction product of claim 7, wherein thequaternizable tertiary amine is a compound of the formula (3) in whichat least two of the R_(a), R_(b) and R_(c) radicals are the same ordifferent and represent a straight-chain or branched C₁₀-C₂₀-alkylradical and the other radical is C₁-C₄-alkyl. 13: The reaction productof claim 9, wherein the quaternizing agent is at least one loweralkylene oxides in combination with the hydrocarbyl-substitutedpolycarboxylic acid. 14: A process, comprising inhibiting corrosion ofiron, steel, a nonferrous metal surface, or a combination thereof, bycontacting the iron, steel, a nonferrous metal surface, or a combinationthereof with the reaction product of claim
 1. 15: The process of claim4, wherein the fuel is a diesel or gasoline fuel. 16: A process,comprising inhibiting corrosion in a fuel having a content of alkalimetals, alkaline earth metals, zinc, or a combination thereof, of atleast 0.1 ppm by weight, by combining the fuel with the reaction productof claim
 1. 17: The process of claim 16, wherein the alkali metals,alkaline earth metals, zinc, or combination thereof, are selected fromthe group consisting of sodium, zinc, magnesium and calcium.